CN1042110A - The method of drawing plastic film and device in stenter - Google Patents

Abstract

By each dolly being advanced to a second speed that stretch section is spaced intermediate at a stenter from first speed of heap row adjacency the dolly collection sections along opposed loop, and be advanced at heap row and form third speed in the section, form section at these heap row, these dollies turn back to first speed in the heap row.Generate electromagnetic waves with first primary coil of the adjacent setting of a part of each loop and to be used for engaging the synchronous secondary coil that is connected on the dolly initiatively, thereby for these dollies provide controlled spacing, and second primary coil adjacent with another part of loop produces other electromagnetic wave, be used for engaging be connected to initiatively and driven carriage on the magnetic hysteresis secondary coil, thereby provide the controlled degree of joining for these dollies.

Description

The method of drawing plastic film and device in stenter

Technical field involved in the present invention is to be used for the stenter of drawing plastic film, particularly about adopting the method and the device of linear motor drawing plastic film.

Particularly the present invention relates to by advancing the active dolly to come oriented film by the tentering iron that is connected with synchronous linear motor.These identical motors also are used for advancing many these dollies with controlled speed and in collection sections before entering stenter.The magnetic hysteresis linear motor is used for these dollies are pushed in the heap row, and the present invention also provides a device to be used for after finishing drawing process returning side by means of the passive dolly of lazy iron propelling along stenter in addition.

As the above, method of the present invention and device at first are to be used for a thin plate or the film of stretching in stenter.Tentering iron by advancing the clamping film in couples with ever-increasing speed at the opposed track in machine direction (MD) upper edge to be to separate each other oriented film with paired tentering iron, thus oriented film longitudinally.Taking place laterally when tentering iron is advanced along the diverging to part of track, (TD) stretches.

In the United States Patent (USP) 3890421 of Habozit and open 48-38779 of Japan Patent and French Patent (FRP) 2317076, the typical method of oriented film by this way has been described.Yet, openly do not provide this invention required interlock meticulously in oriented film according to these and control.In such invention, directly opposed paired tentering iron is pushed into accurate interval is arranged with the phase same rate with adjacent, opposed tentering iron each other, and keeps its relative positioning simultaneously, and this process is finished by adopting synchronous linear motor.

Particularly in tenter frame apparatus of the present invention and method, two circular orbits are active dolly guiding separately in loop, and these loops are put toward each other, and film passes through between loop.Secondary coil is connected on these dollies synchronously, and tentering iron also is connected thereto the edge with the clamping film.Elongated primary coil is put on the film stretching side or front side that is arranged on each loop toward each other, and the synchronous secondary coil on they and the dolly is adjacent, electromagnetic ground and secondary coil coupling mutually synchronously.In the effective coverage of invention, each primary coil comprises many groups of coils, and in the size of the coil groups in a primary coil and another primary coil, opposed coil groups matches, and each relative coil groups is with being electrically connected and having formed single control district.Power is provided to these control areas and is used for connecting stenter by each control area and from a control area to next zone, to advance opposed paired dolly symmetrically, as in common stenter, track in each loop can diverge to, and simultaneously advance the dolly of clamping film edge along track with dolly can be in machine direction and laterally separated.This film is axially stretched by two simultaneously thus.

Synchronously secondary coil guarantee initiatively dolly synchronously coupling or locking thereon, the electromagnetic wave that is produced by primary coil is produced by control instruction.Therefore, as long as dolly is supplied to the front side of loop continuously, preferably with in the controlled speed propulsion reactor row, relative coil groups in each control area just receives the alternating current that is produced by identical predetermined control instruction simultaneously so, these identical predetermined control instructions and adjacent control area instruction interlock simultaneously, along with the front side of these dollies along two loops advanced continuously, they still can keep symmetry.

The method that above mentioned technology does not have explanation or suggestion just to describe.

Habozit patent and relative French Patent (FRP) have only illustrated a closed circuit linear motor system, wherein along the magnetic field winding that relative loop is controlled respectively the dolly that has film are quickened through the tentering case.Inductive secondary is connected on each dolly, advances these dollies to run through loop.Do not mention the symmetric motion that how to obtain relative tentering iron, do not mention how solving the abnormal problem that control has many dollies of the synchronous secondary coil that is joined yet.

The open 48-38779 of Japan Patent has only illustrated a kind of device, it be used for " short core pattern linear motor " in relative loop propelling tentering iron with oriented film.But do not provide the device that is used for guaranteeing relative paired iron realization symmetric motion.

By this controlled symmetric motion is provided, the present invention improves at the technical of tentering iron.

The invention still further relates to the use of linear motor, this linear motor in closed circuit dolly from the outlet of dolly collection sections advance reach the second level or with bigger speed dolly is separated (wherein this dolly collection sections dolly the heap row with constant synchronization speed in abutting connection with motion).After this dolly is pushed and gets back in the heap row before the outlet that arrives collection sections.Determine by the speed in the dolly collection sections in the movement velocity that contacts the back dolly with the heap row in abutting connection with dolly, the dolly that has just arrived the heap row constantly is pressed on dolly, is non-synchronously moving with these dollies after the heap row contacts and before the inlet of arrival collection sections.

Move in the heap row by the magnetic hysteresis secondary coil control dolly initiatively that also is connected on the dolly.These secondary coils come coupling by electromagnetic wave, and this electromagnetic wave is to be produced independently by the zone with the linear motor primary coil of the adjacent setting of magnetic hysteresis secondary coil.Its speed of these electromagnetic waves variable acceleration and deceleration with the control dolly.

In addition, according to a further aspect in the invention, in each loop of stenter, one or more passive or lazy iron can be placed between each tentering iron initiatively to reduce film edge burr phenomenon, for example shown in the French Patent (FRP) of mentioning in advance 2317076, the dolly that these passive iron are housed in the film stretching process is not applied in power.Such driven carriage advances by the active dolly that has synchronous secondary coil on it at first.When the active dolly separates oriented film, then in the front side of stenter by passive iron and the film that the moves passive iron of incompatible propelling that joins.

After unclamping film, before turning back to the processing film section of stenter with these dollies with initiatively dolly returning in the heap row that side turns back to dolly along loop.This realizes by the magnetic hysteresis secondary coil is connected on the driven carriage.These secondary coils are adjacent with identical primary coil, and these primary coils engage with the magnetic hysteresis secondary coil on dolly initiatively.Its effect of electromagnetic wave that is produced by this primary coil is to advance dolly and push during this heap is listed as along returning thruster before dolly arrives those parts heap row that just are being pushed in the dolly collection sections adjacent with the inlet of stenter with constant controlled speed.Adopt the magnetic hysteresis linear motor to advance dolly and push in the heap row of dolly in the thruster of returning of loop, this is an important feature of the present invention.

Certainly learnt linear motor from prior art, and such motor can be used for advancing dolly or rail mounted vehicle in closed circuit.

The United States Patent (USP) 3803466 of Starkey is examples, and it has illustrated that employing linear synchronous propulsion system advances the rail mounted vehicle independently in loop.This vehicle or the car team that enters are selectively quickened, and in position are decelerated then so that they move by a station with low speed and at the interval of selecting.

The United States Patent (USP) 3890421 of Habozit is another examples, and it has illustrated that the control of employing Linear-Induction Motor is installed in the two axially drawing plastic films of clip on the dolly, and wherein this dolly moves in closed circuit.And Japanese patent application 48-38779 is another example, and it has illustrated that the employing linear motor advances the two thermoplastics type's synthetic resin that axially stretch of tentering iron in closed circuit.Yet do not illustrate that how controlled dolly is returning on the side of loop.

Be a common practice in addition, provide a load-carrying station in the dolly that in being included in closed circuit, moves or the system of vehicle or start section, herein, as United States Patent (USP) 3,803,466 is described, and dolly moves with low speed and is used for passenger loading or is used for other operation, is accelerated at active section then.At these dollies of this startup section is intensive and usually clustering or be agglomerated into a pile row, for example, and shown in above-mentioned patent.Quicken or complete operation for example after film stretching, these dollies are returned in the heap row or the load-carrying section, to prepare to start once more this operation.

Usually, require dolly in loop, to move and always be in state of a control during by loop.This is particularly correct when usually just being returned to the heap row with these dollies of high-speed mobile or rail mounted vehicle, can take place or have a machine in operation to be affected otherwise damage collision.

Develop various technology and solved this class problem.A kind of such solution is disclosed in the United States Patent (USP) 4675582 by Hommes that agent of the present invention acted on behalf of and Keegan.This patent (here all sidedly referring to this patent) discloses a Linear-Synchronous Motor control system, for example, it can be used to accurately advance the synchronous secondary coil that is connected on the dolly to come oriented film in the front side of a pair of relative loop with ever-increasing speed.This identical system also can be used to returning of this loop dolly be slowed down under control.In this system (wherein little vehicle speed and change at interval),, or must not have more than a dolly sometime in the zone and exist in one group of coil windings that electricity separates of primary coil.The Region control that this restriction needs many elementary zones to link to each other with it.Such system has finished effectively and dolly is run through a closed circuit has advanced continuously, but its equipment cost is high and complicated, especially the heap row takes place returning side, can not need the so accurate Synchronization Control of dolly.

In dolly or rail mounted vehicle propulsion system, dolly position and speed when starting usually are most important.For example, the rail mounted vehicle in above-mentioned Starkey patent suitably moves with selected interval in this position and finishes the load-carrying purpose.Also be so equally in other systems, be included in the Hommes of firm description and the system shown in the Keegan patent, in this system, in constant-speed section, before quickening, control secondary coil in its known exact position with it, this is very important in the operation of system.

The present invention guarantees that dolly heap is listed in the dolly collection sections with moved further and with controlled constant speed adjacency, and the present invention guarantees that also dolly when starting will be in suitable position and they will move with suitable controlled speed in addition.Therefore, this invention provides the improved or method that changes especially to be used for implementing invention as US3803466 and US4675582 returning side.

For oriented film in stenter, the location and the speed of dolly also are primary importance when starting.For example, in the film that stretches, importantly dolly enters stenter with known spacings, and wherein tentering iron is connected on the dolly.Also be so equally in other systems.

Particularly in the process of implementing this invention, dolly must synchronously enter stenter with electromagnetic wave in first control zone, before machine startup, dolly is pressed mutually, and a dolly car body adjacency and a car keep static.This has just formed at interval with known non-variate, and at this interval, the pole pitch of dolly secondary coil is complementary with the electromagnetic wave pole pitch of being determined by the coil in the primary coil.

After this pretrigger, formed the orientation of dolly, and the remainder of loop front side there is not dolly, the tentering function is activated, and dolly will be pushed into one by one and return along returning side along front side and electromagnetic wave synchronised ground.If with the front side that controlled manner stops stenter, then can keep the relative position of dolly and restart not needing to rearrange dolly.

The present invention guarantees that dolly heap is listed in the dolly collection sections and synchronously moves and adjacency, and the present invention guarantees that also dolly when starting can be in the appropriate location and will move with suitable controlled speed in addition.

Tentering of the present invention system also has and is used for changing the MD extensibility and the device of biaxially drawn films side by side continuously.This allows film to pass with low MD extensibility, step by step MD biaxial stretching rate is simultaneously become a higher degree then to be used for continuous operation.Along with the MD extensibility increases, form section and also can change rate of deceleration and heap row length step by step to adapt to many dollies form section to the heap row from the processing film section transfer at the heap row on the side of returning of each loop; Wherein, in general the increase of extensibility also is accompanied by proportional increase in max. speed.This unique features that is used for reliably and promptly changing extensibility also allows rapidly, optimized film stretching rate cheaply, and is used for the new new parts that increase the extensibility that changes without shut-down circuit and production and installation.When factory uses in the biaxial films stenter, after starting, can not change MD simultaneously and stretch, it is same that MD extensibility in the time of when therefore starting and the MD extensibility when being used for carrying out continued operation are had to.Yet, exist when film passes with high extensibility and film to take place tear such problem for some film polyester.And system of the present invention has overcome this problem.In addition, parts that such invention is moved with minority and an open loop (there be not feedback) control system provide moving of car, accurate, predictable control, and without screw and chain or the position and the driving signal feedback system of fixed pitch.This twin shaft simultaneously to the tentering function with extensibility and linear velocity work that may be much higher than in the past.

So, the present invention is applicable to the improvements over the prior art method and apparatus, be used in stenter advancing dolly around loop, and by provide by syncmotor control, the effective film stretched operation with pile and solve the variety of issue that prior art was faced so far in being listed as by using relative hysteresis motor at a low price dolly to be moved back into dolly by guaranteeing with controllable mode.Such invention also guarantee in the dolly collection sections and dolly in part heap row adjacency always, and they also move with suitable controlled constant speed before entering the front side of stenter.

This invention is not only in the technology of linear motor system but also be used in stenter all having embodied bigger progressive in the technology of two axially known systems of drawing plastic film.

Describe the present invention briefly, the invention provides one and be used for the improving one's methods and installing of in stenter oriented film, wherein, with synchronously and the hysteresis motor relative loop that under totally controlling, runs through stenter advance tentering iron.

Fig. 1 is an isometric view of a linear motor propulsion system of the present invention, and this system is used for around remain silent loop or a track propelling dolly or a caterpillar.

Fig. 2 is the isometric drawing of of the present invention pair of secondary coil dolly.

Fig. 3 is the curve map that moves the functional relation of a kind of secondary coil (dolly) speed of situation and position along with secondary coil around closed circuit.

Fig. 4 is just at the Typical Planar figure of this system in given moment, shows the dolly that distributes around closed circuit.

Fig. 5 is used for advancing around a part of loop the plane of first primary coil on a top of dolly.

Fig. 6 is used for advancing around the remainder loop plane of second primary coil of a bottom of dolly.

Fig. 7 is used for curve map linear hysteresis motor and functional relation slippage.

Fig. 8 is when the curve map of secondary coil around the functional relation of secondary coil (dolly) speed of closed circuit when operation three kinds of situations and position.

Fig. 9 is used to pile the curve map that row form two stable characteristic curves of section, shows the effect that changes friction on dolly.

Figure 10 is the top view of biax stenter of while of the present invention.

Figure 11 is the typical section view of two relative loops getting along Figure 10 center line 11-11.

Figure 12 is the typical amplification sectional view of 12 being seen active dollies adjacent at the elongated primary coil of processing film Duan Zhongyu, from Figure 11.

Figure 13 is typical amplification sectional views adjacent at the elongated primary coil of heap row formation Duan Zhongyu, 13 being seen active dollies from Figure 11.

Figure 14 be in the transportation section adjacency and the active of clamping film and the top view of driven carriage.

Figure 15 is at the active that separate and the clamping film of the end of stretch section and the top view of driven carriage.

Figure 16 is the side view of being seen active of the 16-16 from Figure 15 and driven carriage.

Figure 17 is the sectional view of the friction pulley that engages with dolly along the end in the processing film section that the line 17-17 among Figure 10 gets.

Figure 18 is the block diagram of the representational part of control system of the present invention, and based on the Fig. 1 from US4675582.

Figure 19 be along with initiatively and driven carriage around closed circuit operation active of the stenter that is simplified and three kinds of situations of driven carriage (secondary coil) speed curve map to the functional relation of position.

Figure 20 assembles and the detail drawing of the control zone driving of the typical control zone of active section at the dolly of loop shown in Figure 180 being used for, and based on the Fig. 8 from US4675582.

Figure 21 is the plane of a turning point in the elongated primary coil on the loop active section.

Figure 22 is the sectional view of the turning point of Figure 21.

Figure 23 is the control zone drive current control shown in Figure 20 and the detailed view of gate logic.

Figure 24 is the curve map that representative arranged of electric current to the functional relation of time, and how the logic circuit that Figure 23 is shown limits the control zone drives semi-conductive conversion ratio.

Figure 25 is the sketch of stenter loop of simplification that is used for the curve map of Figure 19.

Be used in the linear motor propulsion system of a closed circuit propelling dolly, exist and quicken and the variety of way of separating dolly, but simple and reliable method that still is not suitable for and device are used for controlled manner dolly being slowed down so far, thereby make the mobile new combination of heap column weight.

System of the present invention provides a kind of like this method: produce the electromagnetic wave that the magnetic hysteresis secondary coil that is connected on each dolly is worked by control and a linear motor primary coil of the adjacent setting of dolly and come continuously the dolly that separates to be pushed during a heap is listed as.This primary coil is divided into many group coil windings or zone by electricity, and each winding or zone are independently controlled.Can apply power so that piling on first speed of row and shifting the magnetic hysteresis secondary coil onto third speed from second speed synchronously or asynchronously these zones.When dolly is run into the heap row, advance the magnetic hysteresis coil consequently dolly to be forced together asynchronously in the zone of heap row porch.This just makes the dolly location with known value, therefore can move and make at interval control accurately in succession to dolly.

The present invention in better mode has adopted magnetic hysteresis and synchronous secondary coil to combine, and is listed as to center on loop and to advance dolly to pass through heap.This system provides on the active side of loop and in the continuous predictable control of returning dolly on the side of loop, wherein, the active side dolly of loop at interval and speed be accurately controlled and returning side and can realize dolly controlled adjacency in heap is listed as at loop.Be used in the linear motor control of operating and return side and coordinate, therefore when changing the interval specification, can adapt in the variation of returning the dolly quantity on the side, and not increase dolly or from loop, remove dolly in active side.The control that is used for these both sides also can make at the speed increase on the fore side and return total variation on the side and under braking and accumulation condition and coordinating.

On the active side of loop, control moving of dolly meticulously and consistently by synchronous secondary coil, and move in the heap row by magnetic hysteresis secondary coil control dolly.This of two secondary coils on each dolly newly is applied in the operation of preferred example of this system and played important function.

Secondary coil

In this application, " synchronously secondary coil " be meant it have one or more permanent magnet poles of being present in the magnetic field and with irrelevant its permanent magnet poles that still keeps of the electromagnetic field of effect motor primary coil thereon, and " magnetic hysteresis secondary coil " if be meant it have the one or more temporary transient magnetic pole that is present in the magnetic field and this electromagnetic field for example the electromagnetic field of motor primary coil do not change polarity, this electromagnetic field is not mated with the magnetic hysteresis coil, still keep its temporary transient magnetic pole.In the magnetic field of arranging a strong nothing, the change in polarity of magnetic hysteresis secondary coil is with the polarity (reversed polarity) corresponding to new electromagnetic field.

Because the electromagnetic wave of propagating (after this often being called " electromagnetic wave ") promotes synchronous secondary coil, and when its polarity is consistent with this electromagnetic wave just, when secondary coil did not just have slippage with identical speed, secondary coil can only produce its specified magnetic force synchronously.When moving when poor, secondary coil magnetic force and speed become unsettledly synchronously, and this secondary coil can stop.

When the magnetic hysteresis secondary coil basically with the electromagnetic wave of propagating synchronously during (nothing is moved difference or move difference very low) operation, it can produce first magnetic force at least, or when with the electromagnetic wave of propagating asynchronously (sizable move poor) can produce second magnetic force when moving.Very low moving in the poor zone, this magnetic force is in does not have difference of moving and very big moving between the poor degree.As long as counter-force is no more than its second magnetic force, so it moves with identical with electromagnetic wave or close speed, and this magnetic hysteresis secondary coil can synchronously be pushed into electromagnetic wave basically.The magnetic hysteresis secondary coil also can move propelling asynchronously to be different from electromagnetic speed basically, and produces its second magnetic force continuously and with to move residual quantity irrelevant.When its second magnetic force during greater than anti-magnetic, magnetic hysteresis secondary coil speed will reach electromagnetic speed basically.When its first magnetic force during greater than anti-magnetic, magnetic hysteresis secondary coil speed will reach electromagnetic speed, and its polarity will corresponding with electromagnetic polarity (anti-magnetic pole), and secondary coil will with its synchronous operation.

Put it briefly, secondary coil can only synchronously be pushed into electromagnetic wave synchronously, and magnetic hysteresis secondary coil and this electromagnetic wave are pushed into basically synchronously or asynchronously.In the present invention, after dolly contact heap row and before the inlet of their arrival dolly collection sections, the principle of this back always forces together the magnetic hysteresis secondary coil that is connected on the dolly, wherein moving at dolly collection sections control dolly before the startup of system of the present invention operation.

Closed circuit

Particularly referring to accompanying drawing, Fig. 1 shows the closed circuit of the trolley travelling that just is being pushed into according to the present invention.Such dolly 1 is supported and is directed to by a track 2, and this track 2 is determined the passage of dolly around the loop operation.Upper and lower secondary coil 3 and 4 is connected on each little car body.This track makes secondary coil 3 locate primary coil and track adjacent positioned with 4 with 6 one-tenth fixed ranges with upper and lower linear motor primary coil 5.

Preferably as Fig. 1 and 2 finding, each dolly 1 is essentially mainly " C " shape structure round track 2.In the outside of " C " shape is the first surface 7 that is fit to, and for example is used for fixing the article that will be moved by dolly.

In better example, a synchronous linear motor secondary coil 3 is connected on the 2nd surface 8 at the top of " C " shape dolly 1.Such secondary coil comprises that two have outside sensing to form the permanent magnet 9 and 10 of the magnetic line of force passage shown in 11, and this magnetic line of force passage comprises primary coil 5.Be affixed to a high permeability break iron material 12 for example these magnet on steel or the cast iron separate the distance of the magnetic pole square that equals primary coil 5 with its magnetic pole, λ S, they have formed the 3rd surface 85 that adapts with the shape of the counter surface mutually of primary coil 5.This ferromagnetic material can be common permanent magnet material for example tungsten or chromium magnet steel, or permanent rare-earth magnet alnico alloy (iron nickel aluminium cobalt alloy) for example, the cobalt magnet steel, or be preferably SmCo.

In addition in this example, a last magnetic hysteresis linear motor secondary coil 4 is connected on the 4th surface 13 in the bottom of " C " shape dolly 1.This magnetic hysteresis secondary coil is made up of hysteresis material 15, and it forms magnetic field at its lower surface when in the electromagnetic field that is produced by following primary coil 6.This secondary coil preferably also can comprise a high permeability break iron 14.Yet in some cases, can more easily hysteresis material be fixed to and have low permeability for example on the surface of aluminium or a nonmetallic surface, perhaps this hysteresis material be fixed along the edge that it has the back side.Sometimes also hysteresis material can be fixed on fluting, the high permeability surface.Such variation is commonly used in the hysteresis motor of rotation.The lower surface of this hysteresis material has formed matched the 5th surface 86 of the shape with the counter surface of following primary coil.Dolly body 84 can be made up of high permeability iron that usually also forms break iron 12 and 14 or steel.The geometry of this hysteresis material (thickness, shape, area) is to determine a factor of the magnetic force that produces in electromagnetism magnetic field.This hysteresis material is to have the material of high magnetic hysteresis and can is as top cited unmagnetized magnetic material, preferably unmagnetized iron nickel aluminium cobalt alloy.With primary coil 6 and this magnetic hysteresis secondary coil 4 form the magnetic line of force passage that is similar to the magnetic line of force passage shown in 11 down.This is with the new dolly 1 of two secondary coils 3 and 4 is very important in better operation of the present invention.

The pole pitch of following primary coil 6, λ h needn't be complementary with the pole pitch λ S of last primary coil 5, and because hysteresis material does not have fixing magnetic pole, the pole pitch of following primary coil can be any common magnetic distance.Yet in better embodiment, the pole pitch of upper and lower primary coil is identical, just, and λ S=λ h ^*=λ.

As shown in, on 4 elongate surface of system in rectangular rail 2 of 8 rollers 16 on each dolly, rotate keeping the orientation of dolly, and provide the antifriction operation for dolly along track.As illustrated in fig. 1 and 2, magnet 9 and 10 and the outer surface of hysteresis material 15 and the adjacently situated surfaces of primary coil 5 and 6 closely be separated with the constant distance gap.As shown in, the surface of primary coil and magnet and hysteresis material can be the plane, perhaps this primary coil can have elongated recessed or nonreentrant surface for some is used, and the shape of magnet and hysteresis material is complementary.For example, this magnet can determine that protrudes a surface, and extends on the direction of operation, and this protrusion surface closely separates with the recessed primary coil surface of extending.If it always moves along a radius when the magnetic hysteresis secondary coil is adjacent with following primary coil, this outer surface also can be an annular surface.Usually, its shape of surface that adapts of the outer surface of secondary coil and primary coil should keep a constant clearance between the surperficial and close primary coil surface of the secondary coil that moves.

Preferably as Fig. 1,4,5 and 6 findings, adjacent with track 2 in the part loop shown in 17, the top or first primary coil 5 are set so that the last synchronous secondary coil 3 on each dolly is worked in position.And adjacent with track 2 in another part loop shown in 18, the bottom or second primary coil 6 are set act on thus on the following magnetic hysteresis secondary coil 4 on each dolly.These primary coils advance two secondary coils and three the main acting sections of the dolly that is connected thereto by this system in closed circuit; 41, one active sections 42 of a dolly collection sections and heap row form section 43.To be described in greater detail in the work in these sections later on.

Fig. 4 be by circle represent just around the plane of " snapshot " of the dolly 1 of closed circuit operation.These dollies are shown to be added on upper and lower primary coil 5 and 6.Fig. 5 and 6 is planes of such primary coil (shade is shown), and its relative position of 17 and 18 in loop is shown.

Last primary coil

As shown in Figure 5, last linear motor primary coil 5 is divided into many zones, and for example first area 19 and second area 20,21,22 etc. are able to Synchronization Control to cause synchronous secondary coil 3 in its motion in the dolly collection sections of loop and active section 41,42.The applicable system that is used for controlling such secondary coil has been shown in the US4675582 of aforesaid Hommes and Keegan.

In this patent, the synchronous linear motor primary coil is divided into many groups of coil windings or zone by electricity, and each zone is imposed power and controlled respectively.Each zone imposes power by the regional driver of the converter that has conversion dc voltage so that synchronous three-phase ac power waveform is fed on the coil in each zone.Each regional driver has a zone of controlling with stable state memory and memory access to provide conversion instruction to the regional driver that is used for given operating condition.The predetermined binary translation instruction that these memories in each zone controller include same quantity is to form a converted-wave that can be in frequency tilts between two limit.These stable state conversion instructions are also had altogether the time spent base from the output of All Ranges controller simultaneously and are adjusted as one man to start, and progressively pass through, and finish and restart the access of each memory in each zone controller.In an accelerating part 57 of active section 42 of the present invention, this just makes change speed, repeats the in time coordinated primary coil generation in electromagnetic wave edge to advance synchronous secondary coil by this accelerating part respectively one by one.Such wave frequency is a zig-zag to the function relation curve of time.In this part, in a zone, will never there be secondary coil more than one in certain time.When needs change operating condition, be accessed in the transition memory in each zone controller, this has and is used for advancing several secondary coils, advances the instruction of each secondary coil respectively as needs.When this transition finished, the different stable state of access was repeatedly remembered similarly to advance each secondary coil, because only need remain under the new operating condition.A master controller makes conversion coordination when a control is remembered another in All Ranges.A component computer is coordinated system works all sidedly.

The dolly gathering and the active section 41 and 42 of system of the present invention are closely cooperated, and the dolly in those sections move under the control that is in first primary coil 5 in the loop in this section.In these sections, comprise first area 19, each zone of the primary coil of second area 20 to 22 has its oneself Standalone Drives and controller for example 23,24 and 25 etc., they are electrically connected to these zones respectively and go up and coordinated by a master controller 27, and 40 and computers 51 of base were to form the Linear-Synchronous Motor control system when this master controller 27 comprised one.When controlling when imposing power by zone 19 and by driving and controller 23, this system provides Synchronization Control for the many dollies in the dolly heap row of part adjacency in dolly collection sections 41.When each dolly quickens and when adjacent dolly separates along the active section 42 of loop, this system also can provide independently Synchronization Control for each dolly 1, though shown in the accelerating part 57 of active section, many zones are arranged, but under the simplest situation promptly when dolly in abutting connection with the time, synchronous secondary coil on adjacent dolly is widened to be separated, and accelerating part 57 can only be made up of a long Dan La district of several λ.By this initial width interval, secondary coil can be quickened respectively, and in an acceleration zone at the secondary coil that will never exist sometime more than one.

Following primary coil

The synchronous linear motor system of just describing be high efficiency be used for quickening dolly and also can be used to dolly turned back to the heap row during, the invention provides an improvement system, be used for especially making dolly in heaps in the side of returning of loop.This heap row work is under the control of lower linear motor primary coil 6.

As shown in Figure 6, such linear motor primary coil also is divided into many zones, the 3rd zone 28 for example, 29,30 and 31, so that form section at the heap row of dolly by loop and made dolly obtain controlled deceleration progressively at 43 o'clock, and before the dolly heap that dolly runs into the gathering in dolly collection sections 41 is listed as, make these dollies obtain controlled collision and press.Electromagnetic speed is constant in the primary coil zone under each, do not change, and since always do not occur with dolly on the magnetic hysteresis secondary coil have synchronized relation, so there is not critical phase relation between these zones, this critical phase relation requires accurate waveform to coordinate between these zones.Owing to these reasons, each zone that common motor drives and control can be used to down primary coil 6 is driver/controller 58,59,60,61 for example, and they are electrically connected to respectively on the 3rd zone 28,29,30 and 31 of primary coil.Common conversion hysteria driver preferably is used on this part of system.According to system's needs, its frequency is by computer 51 controls.

As shown in Figure 4, dolly collection sections 41 has an inlet and an outlet.In system of the present invention operation, critical condition is before dolly 1 arrives the inlet of collection sections, will push at the dolly under the control of magnetic hysteresis secondary coil 4 in the mobile dolly heap row.Particularly, form in this part of part 43 by the zone 31 of primary coil 6 down at heap row and to advance these dollies, this zone acts on each magnetic hysteresis secondary coil 4 so that dolly is pushed in the heap row prior to the inlet that arrives collection sections 41 and continuous action pressure so that dolly is pushed away together.

Dolly heap row

In system operating period, mobile dolly heap row are importantly arranged in loop, for example shown in Figure 4.This heap row have big an inlet and a big outlet about 33 places about 34 places." the mobile formation " of dolly or " move heap row " are meant a zone of dolly adjacency, the port of export in the zone of it has in loop has " fix " position, and have the arrival end that enters continuously, be listed as and leave the travelling car of the port of export by this heap.At the port of export of this heap row, these dollies should with one accurately known speed and position synchronously advanced, this speed and position are for example installed sprocket wheel, screw rod or are synchronously acted on linear motor by some that engages with dolly and determine.This just guarantees accurately to know its accurate position and speed, and needn't need sensor or other feedback when needs separate dolly.Heap row 80 do not move around loop self, but an end of heap row can move with the quantity of dolly in the variation of heap row.When dolly moved through the heap row, the dolly in these heap row was all with identical speed operation.In this heap row, between the dolly is constant at interval, and dolly adjacency preferably.Since dolly side by side in abutting connection with or separate the position that redefines heap row end thus from heap row, so be different from the entrance and exit of dolly collection sections, heap list in mouthful and the loop of the port of export in the position change according to the width of these dollies at least.

The dolly heap row 80 of adjacency must be full of dolly collection sections 41 fully, in this section, need synchronously propulsive units heap row.As shown in Figure 4, the dolly collection sections is formed by first retaining zone 19, and this zone is bonded on many synchronous secondary coil 3 on the dolly of adjacency little by little producing a propulsive force, and this power surpasses any other the power on the dolly that acts in the heap row.These other power can be heap row compressing power (form in section produce at the heap row, will explain later on), act on the positive frictional force on the dolly and place external force on the dolly of heap row, and membrane tension for example, system wherein of the present invention is used in the film stretching operation.If all these power that act on the dolly of piling in the row are low, so this dolly collection sections can be than shown in weak point, for example it only extends to 33 in the position from Fig. 4 69, wherein, shown dolly is synchronously advanced by the zone in the active section 20 and 21 in the heap row.Yet a separate areas preferably is provided, and zone 19 consequently provides synchronous propelling for part heap row.Secondary coil 3 on dolly must be always with fixing interval and with synchronously enter zone 19 at the electromagnetic wave that was produced.

The adjacency of dolly is to be used for forming in the section at the heap of loop row secondary coil accurately being fixed to the best way of secondary coil at interval, wherein, magnetic hysteresis secondary coil 4 can be on electromagnetic wave the slippage variable, but in the predictable limit.Because before dolly enters dolly collection sections 41, the power that produces on the magnetic hysteresis secondary coil has formed the gross pressure that makes dolly keep adjacency, so must always the dolly of trailing in the heap row be arranged on before the end of primary coil 6 down.To descend the end of primary coil to be fixed in the loop by 31 end 74, zone, heap is listed mouthfuls 34 in and must also be positioned at greatly after a position at 52 places, and at this place, dolly decelerates to slightly " hypervelocity " greater than heap row speed.This position in loop be not fix but change with given operating condition, will be better understood when discussing among Fig. 8 and 9.Be scheduled to this hypervelocity by the predefined velocity of electromagnetic waves in the hysteresis area 31 of the end that is listed as the section of formation at heap.This speed can be the about 5-100 inch per minute that is higher than by the determined heap row of the electromagnetic wave in retaining zone 19 speed.Impact velocity is determined by the difference between hypervelocity and the heap row speed, but must be kept low to avoid damaging the dolly that enters the heap row.By its effect of hypervelocity of determining with the electromagnetic wave of magnetic hysteresis secondary coil coupling is that arrival end by the heap row advances dolly to enter controlled adjacency state and within the heap row dolly pushed the adjacency state that presses.

By initial little vehicle speed, the dolly gross weight is in frrction load on the dolly and the power (effect of coil current that produced by the electromagnetic wave on a magnetic hysteresis secondary coil, magnetic air gap, the function of slippage and secondary coil geometry) determines the minimum deceleration distance of each dolly.When determining when the heap of loop row form the maximum admissible arrival end of heap column position on the side, must to consider these factors.In most of situations, make great efforts to make all of these factors taken together to keep constant, but the tolerance of machinery cause slightly variation from the dolly to the dolly.Yet, the stochastic behaviour of these variations will be on many dollies one of average out to " constant ".

The arrival end of the dolly heap row of adjacency appears in 32 places before dolly leaves heap row formation section and enters the dolly collection sections.Yet, the speed of heap row by in zone 19, the electromagnetic speed that acts on the synchronous secondary coil 3 sets, in this zone 19, no slippage takes place, and the heap row are with constant known speed propelling.Electromagnetic pole pitch in zone 19 equals the pole pitch of dolly in heaps, so all dollies in this zone can be advanced simultaneously with public electromagnetic wave.Yet to the end 74 in primary coil zone 31 down, the electromagnetic wave that forms zone 31 in the section at the heap row is just producing a power dolly is pushed the state of adjacency on the magnetic hysteresis secondary coil 4 on each dolly from an end 34 of heap row.Therefore this magnetic hysteresis secondary coil heap row power must keep synchronously propulsion reactor row always less than total pullout forces of the synchronous secondary coil in the heap row.Promptly wherein heap is long increases and just be pushed at the more magnetic hysteresis secondary coil of heap row for different operating conditions, and the power that can reduce to be produced by each magnetic hysteresis secondary coil is to keep below total magnetic hysteresis heap row power of always pulling out heap row power synchronously.Also needing these total magnetic hysteresis heap row are tried hard to keep holds lowly to avoid the high contact force between the dolly.

System's summation

Generally speaking, the present invention includes of summary, one advances the system of dolly, utilizes a linear motor, by on a ring rail 2, promoting dolly, make dolly from the stacking states of its collection sections 41 to its state at interval, return its collection sections.This system, in most preferred embodiment 1, comprise, one along first primary coil 5 of track first setting and second primary coil 6 that is provided with along the track second portion, this dolly is guided around track, each all has one to be arranged on the magnetic hysteresis secondary coil 4 that first primary coil, 5 contiguous synchronous secondary coils 3 and are arranged on second primary coil, 6 vicinities, each primary coil all has control device, thereby, first primary coil 5 advances dolly by collection sections 41, and make it accelerate to state at interval from an adjacency state, thus, second primary coil 6 slows down dolly, push it to the adjacency state of motion heap row, and before the inlet of collection sections, be adjacent to the dolly of this adjacency.

The inlet of dolly collection sections 41 is arranged on the head end of first primary coil 5, moves the dolly of trailing that heap is listed as in abutting connection with dolly, always before the end of second primary coil 6.

In addition, in the present embodiment, first primary coil 5 has the coil of electrical subregion, comprises that first area 19 and a series of second area 20～22, second primary coil 6 also have it electrically to be divided into the coil in a series of the 3rd zones 28～31.

The basic operation unit of system comprises that a dolly collection sections 41, one active sections 42 and a pile row form section 43.The dolly collection sections has an inlet and an outlet, and an end 32 of the first area 19 of first primary coil 5 is positioned at the vicinity of dolly collection sections 41 inlets.And the other end 69 preferably is positioned at the vicinity of this dolly collection sections outlet.In addition, in the present embodiment, an end of first of a series of second areas 20～22 of first primary coil 5, the top of contiguous active section 42, and last the other end of a series of second areas of first primary coil 5, the terminal point of contiguous active section.A series of the 3rd zones 28～31 of second primary coil 6, the formation section of contiguous heap row.There is the device that independently generates electromagnetic waves in each zone in this system, controls to promote dolly 1 by all sections.

By new method or method of operating, said system is applicable to and promotes dolly around loop, and enters and be listed as by a pile.In most preferred embodiment, do to promote dolly like this, magnetic hysteresis and synchronous secondary coil 3 and 4 linear motor are arranged with one, be contained on the dolly 1, this dolly is operation continuously on a loop of being determined by guide rail, and is promoted by the distinct area of the primary coil of the linear motor of adjacent tracks.The method comprising the steps of:

With first constant speed, in dolly collection sections 41,, promote to be in a pile row dolly of syntople by acting on synchronous secondary coil 3, dolly is advanced along the first area 19 of first primary coil;

At active section 42, by acting on synchronous secondary coil 3 one by one, make first speed of dolly from the dolly adjacency, accelerate to dolly second speed at interval, so that promote dolly along the second area or the zone 20～22 of first primary coil;

Form section 43 at dolly heap row, by effect magnetic hysteresis secondary coil 4, make dolly decelerate to dolly from dolly second speed at interval and abut against together third speed, this third speed is greater than first speed, so that promote dollies along the 3rd zone 31 of second primary coil at least;

Form in the section 43 with before the dolly of adjacency contact at heap row, along the part in the 3rd zone 31, with third speed, basic synchronization ground promotion dolly; And

Form section 43 at the heap row, along the another part in the 3rd zone 31, promote dolly asynchronously, force dolly to enter in the dolly of adjacency to produce an abutment force, the dolly of these adjacency moves with first speed.

The present invention comprises that also the dolly at a series of intervals of control promotion enters the method that the mobile heap in abutting connection with dolly is listed as, comprise step, use a linear motor, promote the heap row of adjacency with first speed, and before dolly arrives at the dolly of trailing in the heap row, promote dolly at interval by the third speed bigger, make this dolly be pushed with collision controllably and pile row and abut with the dolly of adjacency than first speed.

The present invention also comprises, utilize a linear motor, the dolly that control promotes a series of intervals enters the method that a heap in abutting connection with dolly that moves is listed as, comprise step: form section 43 at heap row, arrive at trail dolly before, to promote at interval a dolly with the synchronous third speed of an electromagnetic wave basically, this is trailed dolly and moves with first speed low than third speed in the heap row, and, after dolly arrives at the heap row, promote these dollies asynchronously with respect to the same electrical magnetic wave in heap row formation section 43.In the method, linear motor comprises that a primary coil and at least one magnetic hysteresis secondary coil are contained on each dolly, and the dolly of adjacency synchronously moves with respect to another electromagnetic wave with first speed in the heap row.

The present invention also comprises method: the relative electromagnetic wave of a part at the heap row promotes dolly asynchronously and synchronously promotes dolly at another part of piling row with respect to another electromagnetic wave.The electromagnetic wave that dolly produces with respect to the zone 31 of the primary coil 5 of bottom is promoted asynchronously and is synchronously promoted with respect to the electromagnetic wave that the zone 19 of top primary coil 5 produces.

Before dolly enters dolly collection sections 41, the 3rd zone 31 of bottom primary coil acts on magnetic hysteresis secondary coil 4, enter the heap row to promote dolly, in this process, this secondary coil and relevant primary coil are together, at this pith of whole system, played the effect of a magnetic hysteresis linear motor.

The magnetic hysteresis linear motor

In more detail, a magnetic hysteresis linear motor produces approximately constant power a big differential scope, and promptly in sliding, its speed is between second speed and velocity of electromagnetic wave.As with motor arbitrarily, electromagnetic speed is by the frequency definite (velocity of electromagnetic wave=2 λ f) of alternating current in the fixed pole spacing (λ) of primary coil and the coil.The dynamics that is produced by the structure of hysteresis motor is by the decision of the magnitude of current in the primary coil, and this primary coil generates electromagnetic waves and acts on the magnetic hysteresis secondary coil.The typical figure of linear hysteresis motor power and sliding relation curve when Figure 7 shows that given coil current.Dynamics and slope of a curve will change with electric current, and for example also sliding with the curve at 75,76 places has a little variation.

Seen as Fig. 7, zero when sliding, and magnetic hysteresis power does not remain on its second dynamics 87 and 88, but approximately+/ scope that-3 λ/sec slides in decay, the actual characteristic of this zone curve is uncertain, does not therefore illustrate.Slide or synchronizing speed zero, the property class of motor is similar to a permanent magnet synchronous motor, and the power of generation just in time is enough to the load of balancing motor.In the present embodiment, the frictional force that acts on dolly is shown in additional 77,78, so that relatively.The left side at figure, hysteresis motor and frictional force act on same direction, therefore, they are worked together, and dolly and minimizing are slided to slow down, right side at figure, they act on opposite direction, if slide (shown in 78) zero, frictional force is greater than first motor force 81, frictional force will make dolly slow down always, just slide for slow and appearance than electromagnetic wave up to dolly.This moment, system was in the work of the right side of figure, slowed down with dolly always, and sliding increases, and hysteresis motor power increases, and equaled frictional force as 79 places up to it, occurred dynamic balance and sliding stability then, and frictional force no longer makes dolly slow down.This moment, the dolly velocity-stabilization got off, or basically with shown in the low speed of about 1.4 λ/sec slide and to follow electromagnetic speed, when this velocity of electromagnetic wave and little vehicle speed in fact during coupling, this substantial condition of following need not occur, but but it occur really in predetermined low-speed slip place time and again.If the frictional force at 81 places is little than first motor force, little vehicle speed in fact will with the velocity of electromagnetic wave coupling, stable at this, substantial following under the condition, particularly when dolly during with actual this electromagnetic speed synchronous operation, the influence of random variation is eliminated basically between the dolly, and all dollies move with essentially identical speed, this obviously is a kind of ideal situation, and this situation has prevented the dolly collision.

Adopt the possible operator scheme of a magnetic hysteresis secondary coil motor in order to simplify, can be by following operation:

" in fact synchronous " or " synchronously "-when about 81 and 87 places and slip in Fig. 7 are zero apply external force than the power of first level hour, and this is possible;

" basic synchronization "-when apply external force than Fig. 7 in second level at about 87 and 88 places low, foreseeable slip has when slightly changing than low value with load, is possible;

" asynchronous "-when apply external force than Fig. 7 in the second level height at about 87 and 88 places, when sliding, be possible with the load marked change.

System's operation

When dolly was slowed down, this linearity hysteresis motor produced the power of a reverse substantial constant in certain distance, thereby eliminated the kinetic energy of dolly, and the energy of dolly is by its quality and speed decision.Owing to eliminated kinetic energy, thereby reduced its speed.Deceleration can change with one or both methods.First method is the electric current that changes primary coil, thereby changes the power that acts on magnetic hysteresis secondary coil and the dolly.Second method is to keep electric current constant, so power is also constant, but the distance that change power is acted on.Second method is to realize by change the distance that took place to slide before the magnetic hysteresis secondary coil is followed the tracks of electromagnetic wave in fact.Frictional force effect on the trolley also makes its deceleration, but this normally a kind of unmanageable power, and each dolly also may be different.Therefore, it is desirable to, by operating hysteresis motor with quite high dynamics, it is minimum that the influence of frictional force minor variations reduces to, so that the variation of frictional force is quite little to the influence that acts on the total active force on the dolly.For this reason, the second method that changes deceleration is better, because motor force can remain on one near constant high level.With reference to Fig. 3, will be explained in detail especially this method:

The operation of the present invention's one exemplary systems is best referring to Fig. 3,4,5 and 6.In order to simplify discussion, suppose zero can obtain when sliding and maximum motor force big than frictional force, therefore little vehicle speed equals this velocity of electromagnetic wave, dolly is in fact with synchronous operation.Among Fig. 3, the solid line of speed and location diagram is represented little vehicle speed, and chain-dotted line is represented the velocity of electromagnetic wave of level coil experience, shown in deviation is arranged significantly a little.The initial sum terminal position of curve connects has determined a loop, roughly corresponding to the position among Fig. 4 53.Dolly is by continuous heap row of arranging from the position 33 of the active section 42 of loop, be pushed into interval state to 35 places, move along the heap row formation section 43 of loop together then, enter the heap row greatly about 34 places, and with by the speed of electromagnetic wave control by being in the dolly collection sections 41 of adjacency state, its electromagnetic wave is produced by zone 19, and acts on the synchronous secondary coil 3 in top of each dolly.Dolly is at accelerating sections 57, quicken respectively on top elementary regional 20～22 by the independent top primary coil of controlling 5, the electromagnetic wave that this zone produces plays the effect of accelerating the synchronous secondary coil 3 in top respectively, among the shown embodiment, active section from 69 to 35 has 13 zones that independence is controlled.

Among the embodiment shown in Figure 4,36 dollies are arranged in the loop.Dolly is with the operation of first speed of 22.2 λ/sec, adjoins each other and two centre-to-centre spacing length of a dolly at interval, enters into the accelerating sections 57 of active section 42.At the end of accelerating sections, their distances of 4 dollies of being separated by, and before leaving active section 42, reach last second speed 88.8 λ/sec.Dolly is with certain speed operation and interval variation 4x.The ac frequency that generates electromagnetic waves changes with the crenellation pattern that repeats in each zone, to produce this acceleration.Yet in the commutation portion in the zone of zigzag figure, secondary coil is not or not this zone, and they just increase electromagnetic wave continuously, shown in the dashdotted rake of Fig. 3.In these zones of active section 42, once do not have plural dolly in a zone.

Near active section 42 1 ends, the bottom primary coil is provided with since 70 places, and produces the electromagnetic wave of the bottom magnetic hysteresis secondary coil 4 that acts on each dolly.Last top primary coil electromagnetic wave by zone 22 generations, with its maximal rate, speed operation as 88.8 λ shown in 44/sec among Fig. 3, and when each dolly arrives this zone terminal, promote synchronous secondary coil 3 with this speed, zone 28 the first bottom primary coil electromagnetic wave, with the speed operation of the about 76.9 λ/sec at 45 places, this speed is by the constant frequency decision of the alternating current that produces this ripple in the primary coil.Magnetic hysteresis secondary coil on the dolly will at first slide on this ripple, and reduces speed now at 35 places when it enters heap row formation section.This dolly will slow down continuously, reach about 46 places up to it, the velocity of electromagnetic wave in zone 28.In the zone of slowing down,, once several dollies can be arranged as zone 28.Magnetic hysteresis secondary coil 4 will stop to slide when reaching velocity of electromagnetic wave, and resemble and work the synchronous secondary coil, and dolly is moved with the velocity of wave of 76.9 λ/sec.

Generate electromagnetic waves in primary coil zone, next bottom, shown in chain-dotted line 47, with the speed transmission of 59.4 λ/sec, this electromagnetic wave will play and further make the magnetic hysteresis secondary coil 4 that is arranged on each dolly decelerate to 59.4 λ/sec from 76.9 λ/sec.Primary coil zone, next bottom 30 further makes dolly be decelerated to 33.9 λ/sec, and as 48 places, and its rear region 31 makes dolly drop to a supervelocity, or third speed, as the speed 26.7 λ/sec at 49 places.

Dolly is run into the heap row, and this heap is listed in the zone 31, and approximately 34 places in the position move with first speed, 22.2 λ/sec.In dolly collection sections 41, this heap row speed is by the velocity of electromagnetic wave 22.2 λ/sec decision at chain-dotted line 50 places in the zone 19.Differential, or the stroke speed of when bump dolly between being listed as with heap is 4.5 λ/sec.This speed is low as to be enough to by the common shock absorbing device on the dolly, absorbs as a kind of rubber attenuator.After the bump shock-absorbing, this shock absorbing device should not stop dolly with suitable spacing adjacency, this spacing with promote a plurality of dollies simultaneously, coordinate as a common electromagnetism phase of wave at 19 places, zone of dolly collection sections 41.Because in the zone 19, secondary coil is not independently to quicken, therefore in this zone, they can both be by a common electromagnetic wave driven in synchronism.

For the dolly of given sum in the loop, the variation of heap row length is the result of loop active section dolly interval variation and the variation of reach final speed.If the active section dolly reduces at interval, then this section dolly number increases, and the heap row form section dolly number and reduce, and on the contrary, if active section dolly number increases, then this section dolly number reduces, and the dolly number that the heap row form section increases.

Yet dolly can change in the distribution that heap row form section, and this depends on the restriction of the energy value (final speed that depends on dolly) that consumed and following some " desired result ".In some instances, in loop, wish to make the dolly number reduce to minimum place, can when dolly leaves active section and enters heap row formation section, increase little vehicle speed, make it surpass second speed.This can make the more described heap row of dolly form a section optimal cases that does not produce acceleration will early arrive the heap row.For identical heap row length, when dolly early arrives the heap row, thereby the dolly in heap row formation portion just requires few in the system.The length or the heap of heap row are listed the influence that mouthful position will be distributed by dolly in, and this point will be referring to clearer in Fig. 8 and the discussion afterwards.

Slow down and the heap row

In the deceleration diagram that adopts, in the speed-location diagram when promptly dolly slows down, usually, there are many different figures can obtain ideal results, the critical parameter that should control is the position of heap row arrival end, must keep two critical conditions:

The first, minimum or the shortest heap is listed a mouthful position " B " in should leave appearance zone 31 as shown in Figure 3 before, last bottom primary coil (magnetic hysteresis) zone at dolly; Otherwise dolly will not be urged together, and the electromagnetic wave with primary coil zone, top 19 does not arrive synchronously, and dolly is just impossible in the control of synchronous accelerating sections thereafter.

The second, maximum or the longest heap is listed a mouthful position in, reaches at dolly before " 0 " position of the front for example of exceeding the speed limit, should not occur; Otherwise stroke speed is no longer controlled exactly, and the variation of little heap row end position promptly causes the big variation of stroke speed, and its result can damage dolly.

These two conditions are still waiting to solve the undetermined accurate operating condition of selection.Other help to reply the district and select the restriction of fixed point velocity of electromagnetic wave to discuss.In the description to above-mentioned hysteresis motor, the best approach of control hysteresis motor is that confining force (being electric current) is constant, and changes the distance of dolly at each regional slowdown, and some " desired result " of deceleration dolly are as follows under constant force:

A. each dolly should be followed the electromagnetic wave in each zone of slowing down basically, then just leaves this zone, so that little vehicle speed is controlled to a given value in each zone;

B. each dolly is after reaching hypervelocity (position reset), should arrive heap row position, actual entry (S), at least the preselected distance P(of being separated by suppose 4 λ) and at least certain pre-selected suppose 10 λ apart from r() just reach minimum one end of heap column position B.This has just created condition for certain variation of position S, and need not reach the limit of two key conditions.

C. each dolly with the supervelocity operation, was reduced to than a certain preset distance u(apart from d and suppose 8 λ before reaching true reactor row ends position) little minimum of a value, the reducing of d value causes dolly more promptly to catch up with heap being listed as.Yet the d value also should be big than P, turns round near a limit avoiding, and this limit is used for changing the frequency setting in the several Control zone of minor variations when being used for mode of operation.Then, apart from d greater than P less than u(4 λ＜d＜8 λ; Actual value comprises dolly number, speed etc., will change with the overall dimensions of system).

D. when when a duty changes to another duty, slow down and always hocket gradually to next zone from a zone in the mode that system is steadily arranged.

E. the heap row should remain in the restriction of other restrictions as much as possible.For this reason, at the little vehicle speed of All Ranges that the heap row are shaped and distinguish, should be high as much as possible, long heap row make the drift that produces maximum on the heap row length in practical operation, have violated first key condition then, cause system misoperation.

This last " desired result " is important one, and it has significant benefits, has promptly strengthened the reliable operation of system.When trolley travelling was followed the electromagnetic wave of constant speed basically, the operation of dolly can be predicted.By keeping high as far as possible constant speed in heap row formation portion, in short distance, slow down rapidly then, dolly arrives at the heap row rapidly and has kept long heap row.Collision opportunity is minimum under high constant speed; Obviously, not collision in the heap row; Slowing down fast makes dolly be subjected to the collision of possible shortest time.In addition, the big motor force that is used for slowing down fast tends to make some to influence at random, reduces to minimum as frictional force.

The regional electromagnetic speed of slowing down is by its driving frequency decision, and it can utilize the control algolithm of any figure place to select.Such control algolithm is to utilize a cover to carry out based on the percentage iterative method of energy consumption in each zone.The energy percentage of a regional internal consumption equal to be used in this zone the to slow down energy of dolly, multiply by obtaining divided by gross energy apart from △ L of taking place to slow down by mean deceleration power F, gross energy is that the power F in a zone multiply by this regional length L acquisition.This algorithm requires at the energy percentage of the zone consumption that each dolly slows down identical.In an iteration, selected one group of possible deceleration area speed, these speed are admitted to a motion model then, and this motion model is based on known decelerative force, and as obtaining from Fig. 7, counting of carriers is by the motion of system.One group of initial iteration determined to slow down place (or that zone) of beginning, last group iteration adjustment consumes the energy percentage in each zone of slowing down, up to the result with restricted (as above-mentioned " desired result ") consistent.

The stability of system

Fig. 8 shows three curves 37,38,39 of the loop medium velocity-position relation that is similar to Fig. 3, is how move actual entry that how to compensate and heap row end position but three shown different speed ratios show system.4: 1 speed ratio (as Fig. 3) of curve 37 expression, but first mode of operation that obtains with lower speed.Note heap row end entrance S, at 135 λ places, and in Fig. 4, S-37 is at 121 λ places, has extended to pile to be listed as in Fig. 3.Yet heap row form the dolly number of section, and are all identical in both cases, but among Fig. 3, dolly slows down from 88.8 λ/sec, its dolly energy much bigger than among Fig. 8, and dolly slows down from 44.4 λ/sec among Fig. 8.Because decelerative force equates preferably that in both cases the power that applies among Fig. 3 will consume bigger energy through long distance.Because dolly can not reduce speed now at a middle part of slowing down the zone, the length in the zone of slowing down and the distribution that numerical value also influences secondary coil." step " of slowing down can only begin 70,71,72 and 73 places as shown in Fig. 3 and Fig. 6 in the porch in zone.

Curve 38 is depicted as the duty that obtains with 5: 1 speed ratio, it has increased the separation of dolly at active section than curve 37, therefore, also increased the dolly number of heap row formation section, this has caused heap row length to have trace to increase, and is shown as the left side that is moved on to S-37 by heap row end S-38.

Curve 39 is depicted as a duty that obtains at 3: 1 with speed ratio, compares with curve 37, and it has reduced the separation of dolly at lever piece, therefore, has reduced the number of dolly in heap row section.This has caused the trace of heap row length to reduce, and is shown as the right side that is moved to S-37 by heap row end S-39.

Although in fact, always it is not synchronous to be used to promote the magnetic hysteresis linear motor of dolly in loop reversion side, and does not adopt feedback, yet it is a stable and system reliably under the predetermined variation of single dolly driving force or frictional force.This is because underlying cause:

1. before leaving each zone, when the magnetic hysteresis secondary coil reached synchronizing speed, the speed of the dolly that each is slowing down was controlled to a setting value in each zone, therefore, had limited the time and the distance that change.

2. drive dolly with constant hypervelocity and enter the heap row, dolly is caught up with, or heap row length changes fast,, therefore, prevented that the arrival end of heap row from arriving off-position to compensate the variation of uncontrolled variable.

3. select form the regional spot frequency that section selects at heap row, heap row arrival end position at first is between two extreme positions that the meeting of having discussed causes operational issue.

For the ability that system compensates voluntarily is shown, importantly to understand, a dolly is a set time that is used to the given duty of the section of synchronous working in the total time that the heap row form the section flower.Because each dolly all leaves active section, enter the heap row and form section, dolly should leave the heap row and form section, enters the heap row, thereby returns active section.Figure 9 shows that at the heap row to form the influence of section noncontrolled variable variation, as the influence of dolly frictional force to the stability of system.

Be the basic status of the system model of setting up the assessment change in friction force, kept the state of the active section of Fig. 3, the numerical value change by supposition dolly frictional force changes the state that the heap row form section.Be the influence of exaggerative defective mode, the dolly frictional force of establishing basic status is 17% of average dolly decelerative force.(normal frictional force is big, as 1 3/4 % of Fig. 3).For this basic status, each regional electromagnetic operating rate (relevant with driving frequency) of slowing down is determined.Among Fig. 9, it is constant that these velocity amplitudes and its dependent variable keep, and average dolly change in friction force is plus-minus 50%, for the basic condition with frictional force of 17%, heap column position S-54 is 75.3 λ, for clarity sake, saved the deceleration curve of basic status, the result of about 8 1/2 % is reduced to dolly frictional force in 55 expressions of chain-dotted line curve, dolly deceleration this moment is not too fast (because frictional force is also slowed down), therefore, dolly comparatively fast arrives heap row, so as by at the S-55 place to shifting left 7 ^*4 λ increase the heap row gradually and compensate.Yet because the increase of heap row, dolly is longer with lower speed operation, institute so that the heap row to form the total time maintenance of section identical, and, set up the new steady-working state of curve 55.

Curve 56 expression supposition dolly average friction power are increased to the inverse state of 25 1/2 %.In this case, dolly more promptly slows down, and spend the long period to arrive the heap row, this heap is classified as to compensate and is shifted to the right to 76.7 λ and has shortened some a little at the S-56 place, yet this moment, dolly was longer with higher overspeed, thereby the total time that makes the heap row form section keeps identical, and, set up the new steady-working state of curve 56.Pay special attention to, under two kinds of situations of curve 55 and 56, heap is listed crucial limit O-55,0-56 and the B that mouthful position S-55 and S-56 do not reach this duty in.

In the state herein, braking section is short, thereby the dolly number that influenced by interval variation is less, and the available several λ of variation that heap is listed mouthful position in record.In loop with long accelerating sections, the accelerating sections of this length also comprises a constant-speed section of growing shown in 44 than among Fig. 3, in this loop, before arriving heap row formation section, many dollies are arranged, but in this case, hysteresis motor is working properly and can adapt to the above big variation of 100 λ that heap is listed mouthful position in easily.

Change on the line

From zero velocity during starts and as shown in Figure 8 from a speed ratio to another speed ratio during, the heap row form each regional velocity of electromagnetic wave of section and should periodically regulate in operating process, this just requires when dolly changes energy (speed) and/or change the interval that enters the heap row, make heap list mouth in and keep a stable status, by driving frequency being adjusted to per approximately 1/2 second new calculated value, constantly revise the velocity of electromagnetic wave that the heap row form section, will form section at the heap row and obtain required stability, little vehicle speed can be learnt by the mode of operation that active section is scheduled to the interval that enters heap row formation section, discuss among Hommes that these are quoted from front and the patent US4675582 of Keegan, component computer 51 control heap row form the adjusting of the driving frequency in section district, and make its mode of operation consistent with active section, this function of computer control system is known concerning the those of ordinary skill in this field, does not therefore need detailed control is further discussed.

Systematic variation

In the scheme of Fig. 1 and loop category shown in Figure 4, owing to have the gap between the end 74 of bottom primary coil and primary coil top, top 32, therefore, the primary coil of linear motor is not to act on one or another secondary coil continuously.

In improved system, form section along heap row, the bottom primary coil also can give prominence to the gap between the zone, with the cost of saving primary coil and make features simple structure.Because dolly is slowed down from a speed that raises, they just have enough inertia to pass through these gaps in the mode that can be scheduled to.Owing to wish to guarantee that dolly is unlikely to " stranded " when opening circuit, the auxiliary equipment or the operation boost motor of certain form can be provided at these gap locations.

In zone 19, the dolly collection sections also can have the gap.For example, because crooked primary coil is made difficulty, involve great expense, zone 19 can be by two straightways the preceding and curvedly forming around curve around locating not have the curved of primary coil of closelying follow.Because the secondary coil on dolly has been filled in straightway and curved section, therefore, two independent straightways are worked can resembling in a zone together, and can mechanically separate with identical pitch, and the dolly of adjacency can be pushed over not afterburning curved section.

Adopt a scheme with synchronous and magnetic hysteresis secondary coil to be described, herein, a primary coil once only acts on a secondary coil.Another is at scheme, no matter when act on synchronous secondary coil, can add a primary coil, utilize identical or different electromagnetic wave simultaneously, also act on the magnetic hysteresis secondary coil, so just have the benefit that additional drives power is provided on dolly, and can be used for hindering breath and the synchronous relevant velocity fluctuation of secondary coil.

Also have a scheme to be, can remove synchronous secondary coil and top primary coil, and, primary coil can be prolonged, to promote the magnetic hysteresis secondary coil fully around loop.In the dolly collection sections, can promote the magnetic hysteresis secondary coil synchronously, to guarantee that dolly is in the known position-time relationship of the each point of loop, side at line loop, both can and be used for the electromagnetic wave band of synchronous secondary coil with identical zone, synchronously promote the magnetic hysteresis secondary coil, also can being used to pile row relatively, to form the mode of side asynchronous and synchronously promote the magnetic hysteresis secondary coil basically.When asynchronous promotion magnetic hysteresis secondary coil, the percent difference of each dolly load of given position in the system should be reduced to minimum, to guarantee the foreseeable operation from the dolly to the dolly.Require each dolly can predict, and each dolly can both repeat by the required time of active side.This will reduce at heap row and form side non-control possibility of collision between deceleration period.

In most preferred embodiment of the present invention, linear motor is because the promotion of whole process, and to promote dolly also be useful but be contained in mechanical sprocket wheel on the dolly and/or screw rod by linear motor in conjunction with one.For example, in a film tentering system, U.S. Pat 3932919 as Hutzenlamb is disclosed, one sprocket wheel cooperates with the dolly of heap row, and use with the non-of a drive unit and be slidingly connected, synchronously promote these dollies with first speed, the speed of its drive unit and position can accurately be controlled, and play a part as the dolly collection sections.Then, by increasing the pitch with sprocket wheel synchro-meshing transmission, with the mode transfer bogie (that is, keeping synchronously) of screw rod adjacency.Screw rod plays the same effect of active section, synchronously makes dolly at interval, and dolly is pushed to second speed synchronously.This place, magnetic hysteresis linear motor of the present invention can be used to connect dolly, and promote these dollies with second speed, and by dolly is decelerated to third speed, make dolly turn back to the heap row, with a controlled impact velocity and heap row adjacency, and dolly is pressed into the heap row, thereby plays a part as the heap row form section.A system has like this saved expensive heavily assorted speed limitation system (being used for this patent) in the loop, adopted the assembly that is used to return dolly, they are the assemblies that reduced spiral pitch and adjustable spiral distance between centers of tracks, this assembly all must change each time, makes it become the assembly that has increased different spiral pitch.For obtaining improved operation, each dolly is provided with a magnetic hysteresis secondary coil, and a primary coil with a series of control areas, can be along the loop setting in position.According to technology of the present invention, can handle the magnetic hysteresis linear motor, make dolly return the heap row.

Stenter

In most preferred embodiment of the present invention, linear motor is used for promoting dolly on the relative whole loop of stenter, and the material coating materials that stretches is as plastic foil.At the active section of loop, control a pair of dolly respectively and make itself and adjacent a pair of dolly at interval, this place's film in the processing film section of stenter by longitudinal stretching.Also has another one embodiment, wherein, by linear motor with the guiding of driven dolly on the whole loop by the dolly of active drive between, driven dolly is assembled and active section does not apply power at the dolly of stenter, form section at the heap row, active and driven dolly are all promoted by linear motor.

More particularly, especially with reference to Figure 10,11,12 and 13, shown in one the device or stenter 901, be applicable to stretching a slice coating materials 961, as plastic sheeting, improve its characteristic.The stenter of Figure 10 is relative by two, the clamping loop 900 of mirror-symmetrical and 902 is formed, this loop makes film move along the advance side of equipment, to transmit in horizontal and machine direction simultaneously, stretch and the stabilization processes film, cross directional stretch (TD) is to make the clamping guided way divorce of each loop and obtain with common mode, the stretching of machine direction is by quickening a pair of active clamping dolly along the advance side of guide rail as 906 and 908, with synchronous linear motor it is separated to adjacent dolly (as 898 and 899) from active clamping dolly, with oriented film between adjacent clip.The driven clamping dolly of Qu Donging is not arranged on initiatively between the clamping dolly, to reduce the fan-shaped membrane edge, when the clamping dolly arrives loop advance side termination, they and friction pulley 993 and 995 join returning side, friction pulley unclamps clip to throw off film edge, and dolly is sent to second primary coil that returns side from first primary coil of advance side, return side initiatively and driven dolly all use linear hysteresis motor deceleration, and in abutting connection with row in heaps, thereafter, leave return side before, initiatively dolly is driven by synchronous linear motor once more.The clamping dolly is circulated again into the advance side inlet, to clamp the film that enters.In (film) side of advancing of each loop, a control system by computer 1018 monitoring, simultaneously and accurately controlling a hundreds of clamping dolly independently, and is brought together all dollies into the heap that returns side be listed as and the collision that do not have damageability.

In the operation of this equipment, a film that stretch is supplied with by supply source 916, as a donor rollers or come from a film casting operation, and is sent to stenter 901 between the elongated circular rails lead ring road 900 and 902 of pair of opposing by proper device.Two loops 900 and 902 symmetries, its assembly minute surface symmetry.For ease of the assembly of description loop, this place, an assembly only is shown in the loop, and another loop will indicate with " ' " of first assembly.Dolly, dolly 906 initiatively for example, 908,927 and 928, be pushed along the advance side 910 and 912 of loop 900 and 902 symmetrically in pairs respectively, be paired dolly as 906 and 908 along straight line 914 centerings, dolly is as 927 and 928 along straight line 925 centerings in pairs, two straight lines of drawing all with two loop advance side between the center line 904 of centering vertical.

The loop of each track has several parts, falls into the advance side 910 and 912 and return among side 903 and 923 of stenter.The first of track has determined a transportation section 918 of stenter, and in this section, before stretching, film is put in order by the temperature that is heated to requirement, and does not allow to occur stretching.The second portion of track has been determined the stretch section 922 of the key of stenter advance side.These parts of track are typically outwards separated from the center line of machine, use so that film laterally also is being stretched when machine direction is stretched.The third part of track is connected with the second portion of stenter advance side.These parts relative to each other, general center line with machine is equidistant, and has determined that betwixt one of equipment stablize processing section 926, the MD and the TD stretching or loose of a small amount of may take place stablizing processing section.Stretch and the stabilization processes section between dividing line 924, with the variation of processing film condition, preferably can on move and in the downstream of stenter, this will discuss afterwards.

First, second of these tracks and third part have determined to constitute the processing film section of stenter advance side 910 and 912 together.By constituting the complete orbit that the 4th part of returning side 903 and 923 makes machine, return side at this, the clip pine scrapping off film of stenter.Return phase is connected the first of track with third part, with complete loop.

With reference to Figure 10, be provided with many active dollies as 927,928,896,897, be used for motion on microscler track loop 900 and 902.As figure, between active dolly 927 and 897 and 928 and 896, be provided with the driven dolly of many as 931 and 933,935 and 937 respectively.Preferably referring to active dolly shown in Figure 12, wherein, initiatively dolly and driven dolly all have dress tenter clip gap 959 thereon.It is used for when it enters stenter 901, clamps the edge of film, and is made it loosen film after by advance side by dolly at it.In the advance side of stenter, driven dolly is at first by carrying promotion secretly between the active dolly, then, when the active dolly separates, and oriented film the time, promoted by the film that is connected.After the film that gets loose, active and driven dolly all are pulled to the position that repeated stretching is operated along the side of returning of stenter.Figure 14 shows initiatively dolly and driven dolly, and as 927,931,933,897, they appear at the transportation section of stenter advance side, their adjacency herein, and clamp the edge of non-stretched film.Among Figure 15, show identical dolly, they appear at the stretching or the stabilization processes section of stenter, and initiatively dolly separates herein, thereby oriented film, and driven dolly owing to clip together with film, are also spurred it by film self.Among Figure 15, intermittent line represents, if there is not driven dolly clip, it is excessive fan-shaped that film edge can occur.

It is coupled that clip dolly initiatively has synchronous secondary coil, they as the advance side of loop 902 and return an end of side, by discerptible first primary coil 975,977,979,981,983,985,989 mechanically and 991 and its inductance coupling.Loop 900 has corresponding first primary coil, the mirror image that becomes of its position and loop 902.Aforesaid Linear-Synchronous Motor control system is used for first primary coil, controls the initiatively promotion of dolly, as along 906 and 908 of the advance side on the track 910 and 912.Computer 1018 is being handled the control of this system.Two advance side connect in some way side by side, when each paired clip during by stretch section and other processing film sections, these paired clips are carried out total control.

Initiatively and driven clip dolly the magnetic hysteresis secondary coil all is housed, they are in the side of returning of two loops, by mechanically discerptible second primary coil 939,941,943,945 in the loop 902 and 947 and its inductance coupling.Loop 900 has the mirror image position with loop 902 corresponding first primary coils.Relatively second primary coil is with in groups on the loop, and they receive the identical operations instruction from computer 1018, realize the purpose of controlling.Above-mentioned linear hysteresis motor control system is used for controlling initiatively and the promotion of driven dolly and heap row, and when the synchronous secondary coil that act on dolly initiatively by first primary coil, as 975 in the loop 902, once more during coupling, keep the pressure adjacency of dolly in the heap row, leave then and return side.

In typical application, material membrane or film 961 form in upstream 916, and by the inlet 920 of feeding stenter.Relatively initiatively dolly, and spurs it and passes through transportation section 918 with constant speed along the fringe region of relative film edge clamp in succession at 920 places after last tenter clip gap, is heated and does not stretch at this film.Be clipped in the driven clip dolly between the dolly initiatively and also clamp the edge of film in the transportation section, and taken away by the active dolly of adjacency.Track is divorced at 921 places, thus the cross directional stretch film, and approximately meanwhile, relative active dolly is to being accelerated respectively, makes itself and adjacent pair of separated, and at stretch section 922 oriented film longitudinally simultaneously.At stretch section, in the shell 895 of baker, film is heated continuously, during stretching, to control film temperature.Then, make the track almost parallel, relative paired dolly reaches second speed at the end of stretch section 924 separately, and film is in the stabilized processing of 926 these sections.The speed of dolly and the extensibility of film can have slight variation in the stabilization processes section.In the stabilization processes section, the control of the temperature of film is continuous, and this temperature control also comprises continuous heating or cooling.Then, in stenter outlet 929, film is released from tenter clip gap, and receives continuously on the common coiling machine.On each loop independently initiatively and driven dolly, by along two dolly loops return side 903 and 923, turn back to stenter and enter the mouth 920.

Loosen or loose film in machine direction in stretching or stable section if want, can slightly reduce speed gradually or one after the other according to any desirable program, thereby obtain film is shunk and the direct control of the uniformity by the active dolly of linear motor control.In the stabilization processes section, by making the convergence a little as shown in 938 of stenter track, the tenter clip gap side direction is drawn closer together, also can carry out loose.

Dolly can be by following assurance along the symmetry of moving between the advance side of loop 900 and loop 902:

Provide a linear motor primary coil on-adjacent each track, each primary coil comprises many group coils, the size coupling of the coil groups that the size of the coil groups of a primary coil is relative with another primary coil, each is the coil electric connection of group relatively, and has determined an independent control zone;

Adorn a synchronous secondary coil on-each active dolly, the secondary coil of installing is handled by an adjacent primary coil;

-provide predetermined Collaborative Control instruction simultaneously to all coils group of each control area of relative primary coil, thereby produce predetermined collaborative electromagnetic wave in all control areas, therefore, promote active dolly paired relatively on two loops symmetrically by each control area, and pass through stenter to next control area from a control area.

Secondary coil is followed the electromagnetic wave that primary coil produces synchronously, and, as long as initiatively dolly is fed to the advance side of loop with embarking on journey continuously, and the relative coil groups of each control area is received the alternating current that is produced by identical predetermined control instruction simultaneously, these instructions are simultaneously collaborative with the instruction of adjacent control area, so, when the advance side of two loops is pushed, will keep symmetry at the active dolly.

Promote the tentering dolly and be similar to Fig. 4 around the class of operation of single loop, the system shown in 5,6.By the promotion of the Waveform Control dolly of predetermined collaborative control area,, open in 675,582 in aforesaid United States Patent (USP) us4 along each loop advance side.

Fig. 4 represents that stenter promotes one of two loops of dolly.The dolly collection sections 41 of Fig. 4 and active section 42 foregoing such work, with control promote initiatively dolly by the advance side 910 of Figure 10 and 912 dolly collection sections 949/949 ' and active section 951/951 '.Heap row form section and resemble and work aforementioned, with the heap row that control promotes initiatively and driven dolly returns side 903 and 923 by Figure 10 form section 953/953 '.Dolly collection sections 949/949 ' work be to promote initiatively dolly by returning the remainder of side.

The control area of stenter loop comprises the relative coil groups of electric connection.This coil groups is such shown in first and second primary coil section branch of loop 902.For clarity sake, in Figure 10, only show loop 902 primary coils and coil groups, but they are also in the mirror image position of loop 900, for ease of discussing, they add apostrophe " ' " postfix notation with the numeral of loop 902.For example, the relative coil groups of following expression:

First primary coil 977 of-loop 902 and 979 coil groups 930, with corresponding first primary coil 977 of relative loop 900 ' and 979 ' coil groups 930 ' electric connection, to constitute a control area A;

First primary coil 983 of the coil groups 932 of first primary coil 983 of-loop 902 and relative loop 900 ' corresponding coil groups 932 ' electric connection, to constitute a control area B;

First primary coil 985 of the coil groups 934 of first primary coil 985 of-loop 902 and relative loop 900 ' corresponding coil groups 934 ' electric connection, to constitute a control area C.

Pay special attention to, coil groups 930,930 ' from two first primary coils that mechanically can divide, its importance will be discussed later.

Just now the coil groups of first primary coil of Tao Luning is adjacent with synchronous primary coil along the active dolly of loop advance side.They are corresponding to the zone among Fig. 4 19,20,21 and 22.Every place that dolly is separated, as active section 951/951 ', the control area is all through sizeization, thereby, for a desirable duty, when promoting the paired dolly of active symmetrically along first primary coil, in a control area, never have a pair of above paired dolly simultaneously.Yet this situation also is not suitable for the first constant speed control area, and as 981,981 ' (Figure 10), at this, dolly is all at interval very near, or with a plurality of λ adjacency of integral body, and with identical speed operation.In these control areas, many paired dollies can be arranged.

Tentering dolly, track, and linear motor

Figure 11 shows that among Figure 10 along the typical cutaway view of the advance side of crossing loop 900 and 902 with the line 11-11 intercepting of returning side.Cutaway view is depicted as initiatively dolly, respectively as on advance side 910 and 912 927/928, and returning 886/887 on side 903 and 923.Baking oven housing 895 surrounds the major part of advance side, and with control heating film, and track shell 888 and 889 surrounds the major part of returning side, so that the temperature of control clip adheres on the film when preventing to begin with clip clamping film, or makes the film quenching.The track shell also plays the effect of the safty shield of travelling car.

Figure 12 shows that the enlarged drawing at advance side 910 12 places of crossing loop 900 among Figure 11.Initiatively dolly 927 illustrates its side view.Figure 14 and Figure 15 shows that initiatively and plane that driven dolly has amplified that Figure 16 is the front view of active and driven dolly.Set guide rail as 942 detour whole loop 900 advance side and return side, and with advance side with return side and link to each other.This guide rail uses attachment supports on frame 962.This guide rail is a deflection structure, makes the turning point smooth curved, and its structure example is as being shown in U.S. Pat 3,456, in 608 and BP GB1,504,450, referring to embodiment wherein.Dolly is by rotatable 8 rollers 944,946,948,950 that are installed on the car body 960, and 952,954,956 and 958 are bearing on the guide rail 942.At MD or vertically (Figure 15 inwards), roller is aimed at alternately and do not overlapped, and dolly is stably supported.This also can be referring to Figure 16, and the roller 944 and 958 on horizontal rail surface is aimed in the vertical, and horizontal roll 946 and 956 is also aimed in the vertical, but leaves at interval with roller 944 and 958 in the vertical, or does not overlap.Equally, the roller 948 and 952 on vertical track surface is aimed in the vertical, and vertical rolls 950 and 954 is also aimed in the vertical, but offset from roller 948 and 952 in the vertical.As long as dolly is stable along the supporting that is free to slide or rolls of guide rail, also can adopt the roller or the sliding part of other number.Interrupted rail set also is feasible.Roller makes dolly near in orbit, and carrying is by load, the tension force by film clamp film, the axial force of motor and the uneven magnetic force between primary coil and the secondary coil of the generation of dolly weight.

Preferably as Figure 14 and shown in Figure 15, two driven dollies as 931 and 933, are assemblied in per two active dollies, between 927 and 897.Driven dolly does not still have the synchronous secondary coil of attaching to initiatively dolly is similar.Therefore, when the typical brake apparatus 997 of active dolly and dolly 927 and 897 and 999 in abutting connection with the time, be installed in to driven cart vertical between the synchronous secondary coil of the initiatively suspention of dolly.As previously mentioned, level on each dolly that is staggered and vertical roller, thus make " nesting " that roller takes place between the adjacent dolly.If use less roller or between dolly, adopt bigger interval, just do not need this " nesting ".Yet, in order to obtain bigger draw ratio, need make the initial gap of film folder tight, so that fan-shaped edge reduces to minimum.

With reference to Figure 14 and Figure 15, each dolly has an elastic dampers, cushion when dolly the heap of loop row form section in abutting connection with the time the controlled collision that takes place.When the frictional force of a dolly change slightly or when the magnetic hysteresis secondary coil and return air-gap between the side primary coil from a dolly when another dolly changes slightly, also can be in returning the control area of side accidental slight collision takes place.Referring to the dotted line of Figure 14 and 15, initiatively dolly 927 has a damper 1001 and impact surfaces 1003, and driven dolly 931 has a damper 1005 and impact surfaces 1007.During operation, adjacent damper and impact surfaces are walked together as damper 1005 and surface 1003, to cushion the collision between the adjacent dolly.Have only when the damper that initiatively inserts between the dolly 927 and 897 all is subjected to limited pressure, brake on the dolly 927 and 897 997 just contacts as shown in Figure 14 with 999.

The film folder

As typically being shown in Figure 12, active and driven dolly all are equipped with film folder 959.Car body 960 has been installed film folder lever 964, and this lever is at 966 places and is rotatably connected.One clamping face 968 can pivot, and to be pressed against on the anvil block face 970, this anvil block stops the motion around pivot, thereby clamps film.Film 961 is clamped by force in lever 964 on arrow 972 directions, and is loosened by force in lever 964 on the direction of arrow 974.The upper end of lever 964 forms the cam that is right after surface 963 and 965.Among Figure 10, cam face 967 and 969 acts on the surface 965 of dolly in the porch of stenter, come shift lever with clamping films, and in the exit of stenter, friction pulley 993 and 995 circumferential surface act on the surface 963 of dolly, come shift lever, to loosen film.Between lever 964 and dolly body 960, can connect the tensioner as spring, the position of opening and clamping of keeping clip, like this, clip just under the effect of cam face, is forced into the position on opposite.Preferably adopt this device,, open and clamp clip so that only need cam 967,969 and friction pulley to be set at the entrance and exit of stenter.The longitudinal size (Figure 12 inwards) of surface 968 and anvil block 970 is very narrow, when being stretched between clip with convenient film, allows film that lengthwise movement is freely arranged.Learn that film is also had longitudinal stretching by the place of clamp.Be used for the clip of biaxially drawn films simultaneously, open in aforesaid stenter patent and U.S. Pat 3,391,421, need not be further explained again.

Secondary coil

Among Figure 12, initiatively synchronous secondary coil 976 and 978 have been installed in the top and the bottom of dolly body 960.They are similar to Fig. 2 and U.S. Pat 4,675, and 582(is with reference to the embodiment of front) the middle synchronous secondary coil of describing.Among Figure 12, they each all form by the protector at magnet that places 980 and 982 places and 984 and 986 places, be similar to secondary coil shown in Figure 23.Preferably shown in Figure 14 and 15, the magnet at 980 places comprises arctic magnet outwardly and the second adjacent magnet, the second magnet South Pole outwardly, they are 1 λ at interval.As shown in figure 14, referring to secondary coil 927 and 897, preferably be configured to opposite with the magnetic pole of adjacent active dolly secondary coil.When adjacent active dolly the time, i.e. in this stenter invention initiatively dolly car body adjacency the time,, described in 675,582 patents, the spacing of 1 λ is arranged between the secondary coil magnet edges as US4 at its minimum distance.The magnet of the top secondary coil 976 in the left side of advancing referring to the single active dolly as 897 so all has the identical utmost point outwardly with the magnet that dolly advance side left side is positioned at bottom secondary coil 978.For example, in the left side of dolly advance side, top and bottom secondary coil all have the arctic.Shown in Figure 14 and 15, the center line 1009 of the best relative orbit of magnet tilts.This will help eliminating the change of power on trolley, and this change is owing to attraction causes that perpendicular to the profile of tooth stratiform primary coil of track centerline this primary coil as shown in figure 21.Initiatively the best magnet bottom dolly of the magnet on dolly top is towards opposite.Be preferably in top and side, with nonmagnetic conductive shell 1001(Figure 14) magnet cover is got up, as with copper or aluminium on the magnet cover, and provide dynamic electromagnetic buffer (for clarity sake, having saved thin loam cake among the figure) to the dolly that moves.By making adjacent active dolly 927 and 897 brakes 997 and 999 adjacency, in fact between the active dolly, formed the no die opening of 1 λ.

With reference to Figure 12, under the film folder, initiatively 940 places, position on the dolly inclined surface are a magnetic hysteresis secondary coil, and it is similar to the magnetic hysteresis secondary coil of discussing according to Fig. 2, and it is made of the hysteresis material 936 that is installed on the protector of forming dolly car body 960.On the identical therewith relevant position of driven dolly, a magnetic hysteresis secondary coil is arranged also.The high coercive force magnet of the preferably unmagnetized Alnico V(of hysteresis material), as shown in figure 12, it has identical thickness and height on active dolly and driven dolly.Figure 13 is the enlarged drawing that crosses 13 places that return side 903 of loop 900 among Figure 11.Among Figure 13, at 940 places, position of active and driven dolly, the magnetic hysteresis secondary coil is adjacent with second primary coil (943 '), so that be coupled by the electromagnetic wave of second primary coil.Owing to initiatively usually have different quality with driven dolly, therefore under identical speed, has different kinetic energy, the size of the magnetic hysteresis secondary coil on dolly separately is different as appreciable among Figure 16, and Figure 16 is the cutaway view of 16-16 intercepting along the line among Figure 15.The magnetic hysteresis secondary coil illustrates with cross spider, can see at this, and initiatively the zone 1023 of the zone 1021 more driven dollies of dolly is wideer.When the electromagnetic wave by the second identical primary coil is coupled these two secondary coils, want big in the power that the force rate that produces on the active dolly produces on driven dolly, this bigger power is directly proportional with the quality that initiatively dolly is bigger, and because therefore a=F/m makes two dollies decelerations (negative acceleration) under identical speed.

Arrange the initiatively secondary coil of dolly

Steel folder dolly initiatively must be with known interval, and with the first control area A(reference coils group 930/930 ') electromagnetic wave synchronously enter stenter.Before the machine start car brake one of dolly with adjacency is being pressed against on another, and first active dolly is keeping static as 921 places.This has just formed at interval with a known definite value.The pole pitch of dolly secondary coil is with the winding of this value coupling by primary coil, as the electromagnetic pole span of first primary coil 977/979 and 977 '/979 ' decision of forming control area A.Can adopt various devices that dolly is pushed away together, as linear motor device, belt conveyer, gravity installation etc.In illustrated embodiments of the present invention, returning on the side 903/923, adopted linear hysteresis motor.Because the active dolly that optimum device has two different magnetic poles therefore as previously mentioned, at 921 places of two advance side 910/912, must be provided with the active dolly of suitable magnetic pole.For example, in the collection sections of dolly advance side 910, if the arctic that the starting electromagnetic wave requires a magnet so, in the dolly collection sections of advance side 912, also requires the left side of the arctic of a magnet at dolly advance side 921 places in the left side at dolly advance side 921 places.As optimal scheme, no matter when, the magnetic pole on the adjacent dolly secondary coil is always opposite, and this special arrangement is necessary.Obviously, when employing resembles the dolly of these alternating poles, on each loop, the dolly of reciprocity quantity is always arranged necessarily, during with convenient dolly continued circling loop, keep magnetic pole in turn oppositely.

Preferably the predetermined starting location of dolly can be manuallyd locate by dolly and finish, and is perhaps finished by computer 1018 proper operation linear motor control systems.The program step of used control system is as follows:

1. for example in the transportation section, the start-up portion of first primary coil disconnects; Then, as at stretch section, computer 1018 makes the second portion excitation of first primary coil with the DC current of the suitable polarity of low value, causes three-phase coil to produce fixing, alternation electrode electromagnetic wave along second portion.

2. computer 1018 makes remaining first primary coil, friction pulley and second primary coil, slowly advances all dollies outside stretch and stablize each section, and heap is listed as them on the side returning.Returning the magnetic hysteresis linear motor of side, promoting dolly by the transportation section and enter stretch section, tens the associating power in abutting connection with dolly on the stretch section of acting on up to stabilized electrodes are enough to overcome till the pressure of hysteresis motor.Dolly along second portion keeps stable or fixing coupling by electromagnetic wave.

3. computer 1018 makes the electric current of stretch section first primary coil be increased to the operate as normal value.When dolly is back mobile by electromagnetic wave, a short delay is arranged.

4. computer 1018 makes first primary coil excitation on the transportation section with the direct current of corresponding polarity, makes coil produce the dolly of stable electromagnetic wave coupling adjacency, keeps them stable in homophase, or on electromagnetic wave " pinning ".

5. computer 1018 disconnects the primary coil at stretch section.

6. about 921 places in the end, transportation section in the position, computer 1018 monitoring detectors are found out on each advance side initiatively the type of dolly (arctic forward or the South Pole forward), this detector can detect the physical characteristic on the dolly.If two dollies are the types that are fit to, then arrive step 9.

7. if the dolly at 921 places is incorrect on advance side 912, only on advance side 912, advance the phase utmost point, make dolly progressively forward, up to the dolly that is fit to till 921 places are detected on the advance side 912.

8. if the dolly at 921 places is incorrect on advance side 910, only on advance side 910, advance the phase utmost point, make dolly progressively forward, up to the dolly that is fit to till 921 places are detected on the advance side 910.

9. computer 1018 makes at first primary coil, the friction pulley of stretch section and stable section and returns second primary coil on the side, slowly advances unwanted dolly outside advance side, and is returning heap row on the side.

10. system is resumed now, and dolly can be when hope starting stretches profile simultaneously, with priming speed bring into operation (noticing that in some cases starting stretching profile and last stretching profile may be different, as explanation hereinafter).

11. after trolley travelling, film can pass through in normal way, is installed in the porch of stenter.

After dolly started location formation in advance, the remainder of loop advance side did not have dolly, and the tentering function is started, and dolly will be synchronous with electromagnetic wave, advance one by one along advance side, and returned along returning side, as shown in figure 10.This is similar to the working condition of single cyclic loop among Fig. 4, and this pre-starting system also can be used for so single loop.If the advance side of stenter is stopped with control mode, the relevant position of dolly can be fixed so, and when starting, does not need to rearrange dolly.

Original grade coil

With reference to Figure 10,11 and 12, the first elongated primary coil of stenter loop, the dolly that is present in each loop is assembled and active section.These first primary coils as 985/985 ', comprise primary coil 985U/985 ' U and following primary coil 985L/985L ', respectively with each initiatively the synchronous up and down secondary coil on dolly carry out connecting each other on the electromagnetism.Among Fig. 4, these primary coils are corresponding to last linear motor primary coil 5.The 2nd elongated primary coil of stenter loop, the heap row that are present in each loop form section.At 13 places of Figure 11, second primary coil 943/943 ' be that the diagonal angle is arranged, the magnetic hysteresis secondary coil of arranging with the diagonal angle on active and the driven carriage carries out connecting each other on the electromagnetism.Among Fig. 4, these second primary coils are corresponding to lower linear motor primary coil 6.Stenter first and second primary coils are aligned to the control area respectively, and the control of these control areas, are similar to respectively according to the primary coil up and down 5 of Fig. 4 discussion and the arrangement and the control in 6 zones.

Fig. 2,12,13,21 and 22 and in U.S. Pat 4,675, Fig. 2 of 582 has represented a kind of typical primary coil structure.It is made up of the coil that places groove between the tooth of laminated metal usually.Predetermined alternating current as 992 and 994, is supplied with primary coil by conductor.Utilization is along the primary coil up and down of the selected part of advance side, and giving initiatively, dolly provides maximum thrust.Initiatively dolly is advanced simultaneously by two synchronous secondary coil 976 and 978.Some section at stenter does not need maximum thrust, therefore save up and down primary coil one of them, for example the last coil 977,979,981,989 and 991 of first primary coil may make things convenient for.Like this, primary coil also provides an equilibrium magnetism suction on dolly up and down.Therefore, when saving one, on the dolly load that becomes of the roller of arranged perpendicular heavier, and must corresponding increasing bearing.Primary coil is positioned to and leaves the little spacing of dolly secondary coil, the secondary coil of dolly only by the cleaning gap 996 among Figure 12 and 998 and figure in gap 1013 separately.

Among Figure 12, the bogie side frame 962 that advances also comprises some support plates, when primary coil all exists up and down, is used for supporting primary coil 985 ' U and 985 ' L up and down.These support plates directly connect the rear portion of primary coil, and each all has passage, as 1017 and 1019, are used for circulating cooling liquid, descend with the operating temperature that keeps primary coil.Each primary coil as 985, has the end coil of its magnetic core and encapsulation, provides mechanical protection to coil, and effectively heat is conducted to the cooling support plate from coil.The compound of encapsulation, as the epoxy resin that is full of, silicon resin or ceramic material all suit, as long as thermal resistance that they have and thermal conductivity are suitable for being applied to the heat load on the primary coil.A kind of best method for packing is, and is all besieged except motor one side has the steelframe, is full of motor with aluminium oxide ceramics sand, applies portion or two parts of epoxy resins then.Like this, the volume of filler is filled percentage and is approximately 80%.Such technology is known to encapsulated transformer.Two parts of epoxy resins with the artificial resin of bisphenol-A class and nadic methyl anhydride hardener successfully are used.This frame preferably remains the integral part of motor.Heat in the primary coil is basically from I ²The electric loss of R and the next heat that absorbs since the stove of heating film.Place shielding at key place, some supplementary protection can be provided, avoid the heat on the heating cooking stove.

The wedge shape part

Advance side along stenter has several position, and these positions are beginning portion and ends of first primary coil, as being following primary coil at 920 places, and primary coil on 921 places are, primary coil on 892 places are is primary coil down at 929 places.On these positions, synchronously secondary coil has the stratiform of primary coil iron core iron plate to be adjacent from having air to be adjacent to become.Have been found that on these positions it is favourable that metal wedge shape part is provided.As in typical loop 902, just show these wedge shape parts at 1060,1062,1064 and 1066 places.They make synchronous secondary coil magnet near the leading end of first primary coil with leave its terminal adverse effect minimum.This effect and details on the wedge shape part 26S Proteasome Structure and Function, (another application of submitting to simultaneously with the application) described to some extent in corresponding application, can be in conjunction with reference at this.The side of returning along stenter has several position, in these positions some gaps is arranged, and at these gap locations, dolly does not have controllable propulsion plant that it is worked.Referring to the loop 902 of Figure 10, these gaps are present between the outlet and second primary coil 939 of friction pulley 995, and at each turning, as between second primary coil 939 and 941, between 941 and 943, between 943 and 945 or the like.It is favourable providing the double-wedge part of metal at these gap locations, as in typical loop 902 at 1068,1070,1072,1074 and 1076 places, just show these double-wedge parts, as 1072 among Figure 13 ' with down synchronous secondary coil 978 is adjacent, and act on synchronous secondary coil, so that when dolly inertia deficiency so that dolly when passing the gap, provides propulsive force to cross these gaps with low speed.For making the induced magnetism resistance reduce to minimum, the double-wedge part appear at the high-speed motion dolly in face of.The structure of this double-wedge part is preferably each other stratiform thin plate together, is similar to the iron core of primary coil.The work of double-wedge structure and details are also described in above-mentioned corresponding application to some extent.

The turning

With reference to Figure 10, the track in loop and first primary coil constitute adjustable angle by straight way to be changed, thereby may have many turnings.Because first primary coil is interrupted at the turning, these turnings problem occurring aspect the accurate control that keeps dolly to advance, for example these turnings are present in 921 places and stretching on the loop advance side and 924 places between the stable section between conveying and the stretch section, on each position of another advance side many turnings are arranged also.On each position, when stenter was adjusted to the TD draw ratio of lucky coordination, moving track was to adapt to the variation of angle.Turning on the track also is present on the relevant position of returning side, but because the control of moving of car is moved returning on the side is more coarse, so do not have problems at this.Figure 21 and Figure 22 have represented the enlarged drawing at turning, as 912 places of advance side 910.At the turning, have been found that and save the primary coil most convenient, bending is freely existed, and the metal wire of coil is not subjected to bend repeatedly, so that causes fatigue and fracture at last.Save coil, also make and to remove coil sections in order keeping in repair and not disturb the remainder of primary coil to become possibility.Adopt the following step to make owing to save coil, the electromagnetic force of causing at turning loss reduces to minimum:

-save one of coil to organize mutually at the turning;

-add power supply for the coil on the either side of both sides, turning by identical power waveform;

-overlapping protector is provided at the turning.

The Special Significance in second step is the boundary line, control area, will never appear at the turning.This is that promptly identical waveform is from a single control area because the both sides at turning provide electric power by same waveform as.

Figure 22 is the cutaway view at Figure 21 turning.Each primary coil comprises stalloy layer 1015, and their gummeds also are bolted together, and makes it form staggered groove, as 1020 and tooth, and as 1022, and protector 1024.Winding wire is in the groove shown in 1026 are placed on.In this example, three-phase alternating-current supply herein is used for excitation coil, and adjacent windings A, C and B three-phase form a group mutually of coil.Primary coil 981 ' can clockwise rotate around pivot is perhaps with respect to primary coil 983 ' rotate around pivot center 1028 inhour.At 1030,1032 and 1036 places, all cut out the inclined-plane equally, in the end of each primary coil at turning so that during pivot rotates, give security for cleaning.

Primary coil 981 ' have tooth and protector cut-away portions, primary coil 983 ' remove some protectors at 1040 places at 1038 places.Therefore, 1040 place's primary coils 983 ' the protector energy and the primary coil 981 at 1038 places ' protector overlapping, as shown in the figure.Protector end at 1042 and 1044 places all cuts out the inclined-plane, as the end of primary coil, gives security for cleaning during pivot rotates.One little cleaning gap 1058 is arranged between the protector lap, and like this, when elementary coil was placed on support plate 1046 and 1048, they can freely rotate and not constraint around pivot.These support plates also have the inclined-plane, so that clear up during pivot rotates.

At the turning, three adjacent coils are removed (phantom shown in Figure 22), and they are progressive the removing of normal three-phase from coil, have not had the turning herein, promptly A, a C and B phase coil are non-existent at the turning, have only one to organize coil mutually.It should be noted that fracture between the primary coil of turning or connection appear in the groove and not on tooth, tooth preferably keeps not damaging, because in the magnetic line of force passage of secondary coil, it is a critical elements.For making electromagnetic wave distortion minimum, the electric current in the in-phase coil of the either side at turning must have same frequency, phase place and wave amplitude.This will produce distinctive " the multitudinous utmost point " on these teeth.For guaranteeing this condition, preferably power at the coil of both sides, turning by the same power supply of three-phase alternating current, promptly they are parts of same control.For example be illustrated in all coils in the primary coil 981 ' part in the left side of pivot among Figure 22, and in the loop A at 1045 places, pivot right side, at the coil C at 1047 places with at the coil B at 1049 places, will be within identical control area, this has just eliminated contingent phase shift.If each section of turning either side primary coil, encourage by their own independent three phase mains, just phase shift may take place, this has just known the coil groups of early discussing that forms typical control zone A why 930, is made of two machinery first primary coils 977 and 979 separable, that meet at the turning.

Friction pulley

Figure 17 represents the typical section figure by the friction pulley 995 of outlet, as cutting open along 17-17 among Figure 10.Moving runner has a upper level diameter 1050, and it is applicable to that the cam on the contact stenter folder 959 follows face 963, so that initiatively and driven carriage when passing through under friction pulley, forces clip to be opened.So clip loosens film.Lower horizontal diameter 1052 is made up of an elastic ring 1054, and this elastic ring is forced to engage with rear surface 1056 on active and the driven carriage.Trolley track 942 has the center of radius identical with friction pulley, and next plays operation not being slidably engaged state together when friction pulley and dolly, when making friction pulley rotate about 180 °, keeps dolly against elastic ring 1054.After rotating about 180 °, guide rail 942 is stretching, and pilot trolley leaves friction pulley.Two friction pulleys 993 and 995 pass through mechanical driving device, drive by a single rotation motor 103, the speed of this motor is regulated by computer 1018, work in a predetermined mode, thereby pivoting friction wheel, so that when withdrawing from the advance side of stenter, the superficial velocity of lower diameter 1052 is approaching consistent with the preset lines speed of dolly.Because the joint between diameter 1052 and dolly is friction and unfixing, because by the tooth on gear or the sprocket wheel, so do not require accurate speeds match and location matches, and any spacing of dolly can both be regulated.This is the improvement of carrying out on another known synchronous biaxial films stenter, and provides power by linear motor or other devices.Therefore, herein little following distance and axial tensile rate are determined by a special outlet sprocket wheel.

The control zone

Figure 18 represents the typical wiring figure of all control system of the present invention, and it is based on U.S. Pat 4,675,582 control system.Component computer 100 is equivalent to Figure 10 component computer 1018, keeps in touch by interbus 102 and whole first primary coil drivers and the second primary coil driver and fraction wheel drive device.Detector 101 is the relevant information input computer that enters the stenter film speed, so that the tentering function matches with the previous section of film profile.

Assemble and active section at dolly, along the advance side of stenter, each first primary coil comprises many coil groups, in the primary coil of these coil groups in the loop of sizing so that with relative loop in the coil groups of another primary coil be complementary.Each relative coil groups is an electrical communication, and determines a single control area.These control areas are independent control, and coil groups wherein all receives the instruction of adjustment or same driver simultaneously.The relevant in front primary coil that is used for, in the discussion of the Linear-Synchronous Motor system of Fig. 4, a zone only is made up of single coil group winding, for independent this single coil group winding of control, it needs a regional driver and a zone controller, as having discussed when describing stenter, a control area is made up of relative coil groups winding.

In requiring the stenter scope of high tensile force, be used for a control area of first primary coil of two loops, form by four groups of primary coils.With reference to the control area C that forms by coil groups 934/934 ' (Figure 10), it comprises first upper set of coils, 934 ' U and the second lower coil group, the 934 ' L in active side 910, and the 3rd upper set of coils 934U and the 4th lower coil group 934L in active side 912.With reference to Figure 11, these coil groups are parts of last first primary coil 985U/985 ' U and following first primary coil 985L/985 ' L.Coil groups in control area two is to be electrically connected to control area drive assembly 1000.This drive assembly can be made up of single regional driver, as Figure 18 signal and Figure 20 be shown specifically 136, or form by two regional drivers, a bottom and a lower coil group that is used for each advance side, or form each coil groups that is used for the control area by four regional drivers.Select to use what regional drivers, depend on the power match between the power requirement of each coil groups that the rated power according to a regional driver does not shift.These coil groups can be connected with the control area actuator electrical, or link on a plurality of drivers of series, parallel or series connection/parallel connection, also depend on above-mentioned power match.Control area control device importantly, as be used for 1002 of control area C is public to all control area drivers in this zone.This control area control device is a single control area controller also, and as 128 among Figure 18, or because the controller capacity is, it can be two or more control area controllers.In each controller, deposit identical control instruction in.In best embodiment, control area drive assembly 1000 is made up of single control area driver, Region control apparatus 1002 is made up of single control area controller, 138 of coil such as Figure 18 is illustrated in whole four coil groups in the stenter control area, and Figure 18 picture is the canonical dissection that is used for linear motor stenter control system.

Above-mentioned situation also can be imagined and utilizes the several Control zone to advance dolly.At this, the instruction that is used for these control areas all is identical.For example, at the dolly of transportation section just with identical speed in abutting connection with operation, may be the several Control zone there, control area A for example provides power by control area driver and several zone controller of several separation.Yet these zone controllers will all provide identical instruction to the control area driver simultaneously, and this moment all works in these control areas, advances these dollies equally.For special circumstances, when initial, each control area also can work alone as dolly.

It is the same with the Region control apparatus to be connected to a regional drive assembly as the typical control zone C, and the typical control zone also is connected respectively to regional drive assembly 1004/1006 and 1008 as A and B, and zone controller 1010/1012 and 1014.Be similar to Figure 18, all zone controllers all are connected to central controller 1016.It is equivalent to central controller 108 and centre routine control markers 106 among Figure 18.Central controller and zone controller are also got in touch with component computer 1018, and 1018 are equivalent to the component computer 100 among Figure 18, for clarity sake, and only expression and the getting in touch of central controller 1016 in Figure 10.

The control area that is used for second primary coil is similar, but not exclusively identical with the control area of first primary coil.A control zone D who is used for second primary coil, as elementary coil 943/943 ', preferably by two coil groups, return 890 in the side ' composition as return 890 in side and loop 900 at loop 902.These two coil groups will receive identical control instruction.These coil groups can be connected on drive unit and the driving governor, or each group can have an independent drive unit and driving governor with two drive units and the several driving governors that receive identical control instruction.As shown in Figure 10, coil 890 will provide power by drive unit 1078 and driving governor 1086, coil 890 ' will provide power by drive unit 1080 and driving governor 1088; Two drive units receive the same control instruction from computer 1018.Equally, coil groups 894 and 894 ' will be connected respectively on drive unit and driving governor 1082,1090 and 1084,1092, and will form control area E.

Above-mentioned circuit is arranged and is reflected on the sketch of Figure 18, it has represented two typical second primary coil zone coils 143 and 145, they are connected respectively on drive unit and driving governor 141,139 and 147,149, are used for interrelating with the component computer 100 that is equivalent to the computer 1018 among Figure 10.Because the second primary coil control area is with constant frequency work, and in the same area, simultaneously many dollies can be arranged, thus control require than first primary coil control require much simple.Therefore, just do not need accurately to adjust the instruction that gives a plurality of control areas of second primary coil for central controller.Yet the control area of second primary coil still has to make dolly in the loop of about symmetry, from a loop movement to next loop.But accurate symmetric motion under normal circumstances can not take place in dolly in pairs, does not require accurate symmetric motion yet.

Instruction on the line of second primary coil changes, so that regulate the change of line speed of stenter, or the variation of MD draw ratio, this adjusting comes correction instruction by computer 1018 with fixed intervals and realizes.For first primary coil, during this correction will appear in the conversion work instruction and change.When relating to single loop linear motor control system, this correction is former to be discussed.In the stenter that film only allows to gradually change, a suitable correction is at interval from about 1/2 second to about 10 seconds, and it depends on operating rate.For first and second primary coils, between suitable operation conditions change, before further changing, this system will allow the steady operation one-period to stablize this system.When to the second primary coil correction instruction, all instructions can both change simultaneously, and concerning at the dolly that returns side or just in time enter the dolly that returns side, not significant the interference, this is because the inherent stability of linear hysteresis motor system.

The zone driver

Importantly in each control area, there are enough electric currents to come the dolly of pushing ring around loop.Be suitable for this purpose, a regional driver that utilizes voltage controller was described in our aforementioned U.S. Pat 4,675,582.

When this driver advances dolly very effectively, have been found that the driver that utilizes current controller also can be used for guaranteeing that enough electric currents are always arranged in each control area.For this purpose, U.S. Pat 4,675, the driver of Fig. 8 can suitably be improved in 582.Improved like this driver has been represented schematic form in Figure 20, it provides quick induction constant current controller for this system.The flux of magnetic induction electric current that the present invention need not add, the rotation motor driver of similar type be also in U.S. Pat 4,259, describes to some extent in 620.Therefore, can be at this in conjunction with reference.

Improved driver solves following problem, in the stenter double loop, when a pair of synchronous secondary coil that is pushed into enters empty control zone (not having secondary coil to be present on the coil), there are two kinds of situations that electric current is changed, it is believed that a kind of be the inductance of this control area owing to there being secondary coil to increase on the coil, the secondth, the counter electromotive force of inducting in the coil of this control area.During electric current in the coil of this control area flowed, these effects caused instantaneous voltage drop suddenly, thereby reduced the electromagnetic force that engages secondary coil.Secondary coil (dolly) is when high-speed, and this problem is more obvious, and in a little control area, compares with the λ length of secondary coil to have a little λ length.Between secondary coil and primary coil, in having the more high-power syncmotor of high inductive, this problem is more obvious.When a secondary coil entered a control area, the quick variation of electric current had been passed to dolly effectively to transient pulse power, therefore caused vibration.Under extreme case, this vibration can make secondary coil lose with the control area electromagnetic synchronously, thereby dolly stops.This problem can be by providing a quick response current system, makes it change rapid reaction to counter electromotive force and inductance and overcome, and can be compensated by coil being increased effective power.

Response current control can be finished by following measures fast:

-provide a high effective voltage to the driver switch transistor;

-detect the sign electric current of electric current output with transistor, and determine the difference between detected electric current and the desired current value;

-according to this difference, cut off and connect transistorized instruction, thus the electric current output of adjustment driver, can also comprise the following steps: in the value that requires in addition with the hold-in winding electric current

Frequency is cut off in-restriction, makes it less than the transistorized switch limit, can avoid transistor overheated for this reason.

Figure 20 represents an improved regional driver, and it is similar to U.S. Pat 4,675,582 driver shown in Figure 8.Its voltage control circuit figure has dispensed Fig. 8 of the second bus 531(US4675582 of low-voltage), therefore, only there is a single high-voltage bus 529 to add current detector 550,552 and 554 now, in order in phase coil A, B and C, directly to detect electric current respectively.The output of detector flows to a new region actuator electrical stream controller and gate logic 556, in order to replace US4, the regional drive door logic 520 among 675,582 Fig. 8.Output protection is still by 508 providing on circuit 510.U.S. Pat 4,675, among 582 Fig. 8, the voltage given value of voltage changer and frequency are expressed as in Figure 20 and can separate effectively with 508, and are used for adjusting the Current Control set-point on novel circuit 556 circuits 558 now.

Figure 23 represents this zone actuator electrical stream controller and gate logic 556.The input of representing A, B and C phase current detector on the right side of figure.In the bottom of figure is 3 bits of control information, and their are for along A, the B of the zone controller of logic 500 and the C usefulness of input mutually.In the left side of figure is the input of the electric current set-point of output protection controller on whole three-phases on the circuit 558 and the circuit 510.This output protection is to be used for preventing the break current situation, and this situation can result from the drive part that is damaged, but it is not a theme of the present invention, and therefore for clarity sake, its course of work has been omitted.Outlet line at the top of figure indication circuit 556 is used for sign A, A and B, B and C, the transistor of the upper and lower of each phase of C.Current Control of the present invention is along finishing as these phase control lines that will illustrate.

The all detected independently and control of all three-phase currents, therefore the explanation for a phase will be suitable for other two-phase equally.The control table of A phase current is shown in the left side of Figure 23, and the phase control information of A phase is transfused on circuit 506, and the base of input signal AND gate 560 to the circuit 562 is provided.This information is also carried out conversion by the converter on circuit 566 564, and provides an input signal to the base of AND gate.Information on circuit 562 and 566 is respectively upper and lower A phase power transistor 530 and 532(Figure 20), desired predetermined switch transition mode is provided.Equally, the information on circuit 570 and 572, for B phase transistor provides predetermined switch transition mode, and the information on circuit 574 and 570, for C phase transistor provides predetermined switch transition mode.Yet depend on the actual current value during this mutually, predetermined switch transition mode can be cut off by current control circuit.This current control circuit provides other input information to the base of AND gate 560,568,578,580,582 and 584.

This current control circuit of explaining now, again with reference to the A phase, but it also is suitable for all three-phases.The current value reference signal of wishing is applied on the circuit 558, and as an input signal of A phase comparing circuit 586 bases, wherein comparison circuit is the dead band restriction Circuits System of reference current.

Comparison circuit is determined the difference between the dead band reference current of sensed current and requirement.If sensed current is littler than the reference current of bottom dead band restriction, the output signal of comparison circuit is then low, if sensed current is bigger than the reference current of top dead band restriction, the comparison circuit output signal is then high, if sensed current is within the restriction of dead band, then comparison circuit recovers final output signal.The comparison circuit output signal is in the input signal on two gates 586 of A phase current control rate limit circuit 598 and 588 circuits 590.

Since high pressure always appears on the circuit 529, so that the electric current of requirement is provided, yet, only require high voltage once in a while.Usually on limiting the quantity of, therefore, current control circuit usually disconnects power transistor and connects current signal, to make every effort to keeping electric current within the restriction of dead band.For preventing the excessive conversion ratio of power transistor (this conversion ratio usually by the L/R of phase coil time constant decide), the restriction of conversion ratio is introduced in the current control circuit.It is overheated that excessive conversion ratio can cause, therefore, must avoid appending in the normal transistor heat load.

The current signal of gate 588 compares with the signal that finally receives from circuit 592, and this OR-gate is relatively delivered to the logic circuit 594 that Once is forgivable, twice is not starts.When input signal not simultaneously, as an example, concerning transistor, if electric current is " on ", and its value surpasses the restriction of dead band, top, and then the chip logic circuit outwards carries a signal to give circuit 596, and circuit 596 must be via the timing circuit of the RC element representative that illustrates.Logic circuit 594 prevents that timer from starting again because of state variation, till it fully regularly finishes.These timing circuit 598 limit switch conversion ratios, therefore, current control circuit can be finished and prevent power transistor excessive switch transition under high electric current.The output signal of NOR element 586 is reversed, and becomes other input signals of AND gate 560 and 568 bases.The typical integrated circuit chip useful to this circuit is non-" one shot " chip that triggers again of Motrola, and Part No. is MC145388.

MC145388 is from Motrola Inc.Anstin, TX..As described, the value that constant was determined when current control circuit switch transition rate was sought by L/R inevitably, the time constant change the magnitude of current, but this rate limit circuit that has been provided limits.Figure 24 has represented this result, and this is the exemplary currents time plot that is applicable to an inductive load.Giving the voltage bus of typical inductive load with power, is to be enough to drive current by load, and this electric current is greater than the electric current that requires.For different working conditions, for example for starting with for high-speed continuous operation, current value may be low or high or between them.For low and high electric current, electric current forms in the constant and decay in the time of 4 greatly, yet for when connecting and cutting off at first, high current curve is much steeper than the low current curve.This is because high electric current in the identical time with low current, must rise to a high value and descend from high value.Rising and the decline of high electric current in its dead band, for identical dead band, will be more faster than low current.Therefore, for high electric current, the switch transition quantity that time per unit takes place, inevitable more, when identical dead band restriction was suitable for two current values, the result showed low current at 543 places, high electric current is at 545 places.This shows that for high electric current, intrinsic switch transition rate is much more frequent than low current.Low current speed is acceptable, and that high current rate causes in power transistor is overheated.When the rate limit logic of applied current control circuit, high current trace is with similar dotted line trace 547.

At work, when the middle mutually electric current of the command request A on the line 506 was " on ", because the overvoltage on the circuit 529, electric current can rise, and surpasses the restriction of dead band, top up to it.As 549 on this time, the output of comparison circuit on 590 is elevated to rate limit circuit 598, if this time is owing to final comparison circuit state stops, the rate limit circuit is exported a signal and is given AND gate 560 and 568, cut off A phase current " on " instruction, and rate limit circuit 598 begins regularly in this new state.Then, the electric current in the A phase coil begins decay, and drops to the dead band, bottom, at this moment between, comparison circuit output descends.If the time that speed limits stops, " on " instruction of electric current can be continual, and then coil current will be switched on.If the time of rate limit does not stop, " on " instruction still is cut off, and then electric current continues decay, till the time stops.Under latter event, current trace is similar to dotted line, on dead band restriction and under rise.

With reference to the dotted line trace, speed has been limited to the value of a satisfaction now, but the current strength change is bigger a little than the restriction of original dead band.In fact, narrow dead band restriction has been widened the switch transition that is used for controlling excess for high current value (having utilized the rate limit logic circuit).Therefore, can prevent the overheated of power transistor.If driver is selected low current, when definite switch transition rate, limit in narrow dead band can be governing factor.Even when low current, also allow quick response therefore.The method of this formation rate limit, preferably fixedly dead band restriction for different current values, must be readjusted fixedly dead band restriction, so that in the high electric current of restriction, be more effective, be when low restriction, the identical dead band restriction of the current-responsive that do not slow down.This method for limiting allows driver that maximum current-responsive is provided, and for the special device of condition of work, whatsoever current value can be selected.

In the driver with transistorized converter type predetermined, that shake control power supply, phase control instruction, best circuit has illustrated and can be used to provide quick response current control.Yet within the scope of the invention, other devices also can be used to provide an excess voltage bus, and limit electric current by cutting off predetermined instruction in a control speed.A simplification circuit of being explained, wherein on positive dc bus, only use single circuit detector, and save transistor switch circuit A, AND gate on B and the C (resembles U.S. Pat 4 very much, 259, circuit in 620), this simplification circuit also will be finished same control.Because, an effectively quick response current control circuit is arranged, the coil current of a control area just can be controlled apace, the value that keeps electric current requiring.Like this, can avoid undesirable sometimes vibration the in service of active dolly.

In the stenter control system, linear motor zone driver, for maintenance and part store all be the same easily, still described driver is different for first and second primary coils.For second primary coil, their phase place and frequencies between the control area do not require coupling, and giving the control zone can be that a general changing type can be regulated frequency drives with the driver of power, and has some Current Control form.General gate logic will comprise the device of switching transistor in general manner.Yet,,, always require to have the control area controller of specialized instructions for switching transistor for first primary coil.

Zone controller

In conjunction with the foregoing U.S. Pat 4,675,582 of reference, the control area controller of first primary coil in the stenter control system constitutes according to the zone controller among this patent Fig. 5 fully.These control area controllers comprise one first stable state memory storage, as 404, in order to operate the control area under first steady-state working condition; One second stable state memory storage is as 412, in order to operate the control area under second steady-state working condition; And one the 3rd transformation memory storage, as 408,, realize by of the transformation of first stable state to second steady-state working condition in order to the operation control area.In stenter, be converted to this ability of another steady-state working condition by a steady-state working condition, allow stenter to change the MD draw ratio, do not interrupt from a continuous operation draw ratio to another continuously elongated material film of continuous operation draw ratio while.

Variable draw ratio

Here special feature promptly can easily change duty, i.e. draw ratio, and for the control area, stenter folder dolly advances by this control area and does not stop, and this is the special performance that stenter of the present invention provides.At first, make the stenter starting, and film passes through under a synchronous biaxial stretch-formed ratio of the first low stable state at first.Then, when continuously elongated film, change to the synchronous biaxial stretch-formed ratio of another higher steady state.Secondly, allow the synchronous biaxial stretch-formed ratio of fine setting during operation, so that the flow process optimization, and make film reach inaccessiable quality in the past.This is because the synchronous biaxial stenter of prior art only can change the MD draw ratio that increases progressively by length, and the starting of circuit and shutoff device cost are also high.

The TD of film stretches during operation, also can regulate bolt device by driver intermittently and regulate and finely tune, and it is close to each other and leave to move loop as 907, and at the loop turning, curved in tracks and slip make and adapt to angle and change.This tendency adjustment feature is in U.S. Pat 3,150, shown in 433.At this in conjunction with reference to this patent.Be used for regulating the bolt of stenter width and the nut that rotation is installed, have a right-handed thread section,,, can be used for a loop as 913 and 915 as 911 and nut.For another loop, has a left-handed thread section, as 917 and nut, as 919 and 909.The axial restraint bolt of Zhuan Donging by this way, as 904, it is close to each other and leave in its relative direction to move two loops.A motor as 905, is connected in bolt, and before stenter work and duration of work, by operating personnel's control, makes it finish the rotation of bolt.Therefore, when needed, can change MD and TD two draw ratios and continuous synchronization ground biaxially oriented film.

When low MD and TD draw ratio, film is installed more relatively easily, and when high draw ratio, common experience shows that most thin polymer films are torn easily and ruptured, as the polyethylene terephthalate film.

After film is with low MD and the operation of TD draw ratio, use device of the present invention, can increase the TD stretching by regulating the stenter width, and can pass through switch control the stenter folder of the 3rd conversion work condition, increase MD and stretch.MD draw ratio herein just continuously changes, till arriving the second stable state MD draw ratio.Then, control system can make the control of stenter folder be converted to the second stable state MD draw ratio, is carried out continuous work, like this, allows to move with the synchronous twin shaft MD of height draw ratio.This is impossible in the prior art stenter, because they are only with a fixedly twin shaft MD draw ratio job, when being high draw ratio, film can not be installed.High twin shaft MD draw ratio synchronously surpasses 3X, or is preferably 5X, or 7X and be preferably 9X more preferably.This result in synchronously biaxial stretch-formed film was impossible in single-stage stretches in the past continuously.The meaning of single-stage is exactly the single stretched portion that does not exceed stenter.

Sequence stretching

From this, the longitudinal stretching of film can accurately be regulated according to the present invention, and this is owing to regard to its lengthwise movement, used many linear motors to drive in check paired dolly respectively, and these paired dollies are independent of other paired dollies.Like this, synchronously finish as described in film biaxial stretch-formed resembles, perhaps also can sequentially finish.In sequence stretching, cross directional stretch is prior to longitudinal stretching, vice-versa.If require the cross directional stretch film, be to keep constant at the little vehicle speed of guide rail crotch prior to longitudinal stretching.Like this so that only finish cross directional stretch and after this, the speed of dolly is increased to the longitudinal stretching of film gradually in stable section.If wish this working method, as some size of the winding wire in the control area that is shown in stable section among Figure 10, the redesign of will having to is with convenient dolly when separated from one another, at the dolly that never has simultaneously in the control area more than a pair of.For the longitudinal stretching film prior to cross directional stretch, at the guide rail of stretch section, readjusted to continuously parallel, and in the parallel portion of stretch section, the speed of dolly increases gradually, so that longitudinal stretching to be provided.After this, keep constant in that the speed of stable section dolly is the same with the track crotch, so that only finish cross directional stretch.In addition, there is not cross directional stretch if only require longitudinal stretching, but guide rail from 921 to 929 keeping parallelisms, thus any cross directional stretch of film is not provided.Equally, do not have longitudinal stretching if only require cross directional stretch, track will be as shown in Figure 10 bifurcated, but dolly is all with a constant speed operation, in the whole advance side of stenter, dolly is not separated out all the time.As long as all initiatively dolly moves in abutting connection with ground with identical speed, in the active section control zone, more than one dolly can be arranged simultaneously.

The MD synchro-draw changes

Can obtain many advantages by the present invention, these advantages result from elongated fixedly primary coil in fact and are divided into the several Control zone, these control areas exert an influence to the in pairs synchronous secondary coil of mobile linear motor, so that a predetermined speed gives the active dolly and presss from both sides along primary coil carrying secondary coil and stenter.Like this, because each is independently advanced (promptly being independent of other paired dollies can accurately move) to the active dolly,, can determine an accelerated procedure for cross directional stretch being added on the longitudinal stretching predetermined, control.Therefore, during film moved past stretch section, being added on vertically moving of film can accurately be regulated; Equally, the speed of film can accurately be controlled in conveying and stable section.No matter wherein, initiatively dolly all is separated out, and selects control area length, never has more than one active dolly so simultaneously in a primary coil group of control zone.Therefore, by pre-determining frequency and the phase place that is added to each primary coil control area, the stretching of any hope of film can both be finished, as change the ratio of MD draw ratio and total quantity and MD and TD stretch in stretch section ratio, for example the MD strain rate can be controlled on each position in stenter during film synchronous biaxial stretch-formed.Strain rate definite as follows:

Occur in during the stretching, strain rate or instantaneous strain speed between two different times, the two adjacent clips are determined as follows:

Strain rate (SR)=((L2)/(L0)-(L1)/(L0)) * 100%/(t ₂-t ₁)

SR=per minute strain %

In the formula:

L ₀=time t ₀=0, film when beginning to stretch, film unstretched length between the two adjacent clips.

L ₁=the time=t ₁The time, the tensile elongation of film between the two adjacent clips.

L ₂=the time=t ₂The time, the tensile elongation of film between the two adjacent clips.

Average strain rate (ASR) is the special circumstances of strain rate, the stretching here be from the time be t ₀Unstretched state to the time be t ₂Complete extended state measure, in this case, L ₁=L ₀; t ₁=t ₀; t ₂-t ₀=total stretching time, this result is as follows:

Average strain rate (ASR)=((L ₂)/(L ₀)-(L ₀)/(L ₀)) * 100%/(t ₂-t ₀)

ASR=((L ₂)/(L ₀)-1) * 100%/stretching time

Strain rate can be controlled as a steady state value in whole M D synchro-draw, or it can increase gradually during the MD synchro-draw, and perhaps it can increase then fast and reduces gradually during synchro-draw.Compare with commercial known stenter, stenter of the present invention can produce big 2 to 3 times strain rate.This is because for any given MD stretching distance and strain rate control, and stenter of the present invention can carry out biaxial stretch-formed synchronously with bigger 2 to 3 times than the stretching-machine of any prior art, big sometimes 10 times operating rate operation to film.For example, above-mentioned U.S. Pat 3,150, the stenter of 433 extensive stock forms, only can be less than the muzzle velocity of the continuous film processed of about 500 feet/per minute, stenter of the present invention can reach the muzzle velocity of the film processed of about 1200 feet/per minute.When stretching a film, be with about 1200 feet/per minute muzzle velocity and the synchronous biaxial stretch-formed ratio of 5 * MD in about 9 feet distances, when stretching with constant MD strain rate, the about 32000%/per minute of MD strain rate consequently.

In order to more fully understand advantage of the present invention, the film of polymerization uses different speed, various extensibilitys etc. on Linear-Synchronous Motor stenter of the present invention, simultaneously on MD and TD direction by biaxial stretch-formed.Though, in the plant equipment of prior art, biaxially oriented film is finished on twocouese simultaneously, but in the time of on the equipment that being stretching in of film described, can changing fully synchronously biaxial stretch-formed the ratio easily, just obtain the significant characteristic of film of the present invention-fully synchronously biaxial stretch-formed these films on two-way, and on the plant equipment direction, do not have prestretched, or in predetermined control mode accurately biaxial stretch-formed these films.

Like this, these films can be with minimum 3X, on twocouese, to be stretched to the strain rate up to 60000%/per minute by 10000%/per minute.Film can stretch with minimum 5X preferably; Best film can be with minimum 7X and preferably can be stretched with minimum 9X.Film can be following any material: polyester, for example polyethylene terephthalate and polybutyleneterephthalate, polyamine, polyacrylate, polyolefin, for example low-density and high density polyethylene (HDPE), polypropylene or the like, propylene-ethylene copolymers, Merlon, polyvinyl chloride, polystyrene, polyurethane, polyvinyl alcohol, polyvinyl fluoride, polyacrylonitrile, polyimides, the copolymer of ethene and vinyl alcohol, polyphenylene sulfide, the copolymer of vinylidene chloride and vinyl chloride and copolymer with alkene unsaturation monomer ethylene, as vinylacetate, methyl methacrylate, the ethyl-methyl acrylate, the ethyl propylene acid esters, methyl acrylate, acrylonitrile, methacrylate or acrylic acid and its ionic copolymer.

It is good especially to use by the biaxially oriented polyethylene terephthalate film of the present invention's processing, and can have many beyond thought desirable features, as having high mechanical strength, low-down heat-shrinkable and fabulous dimensional stability, these features will make it be used as the attractive alternative of basement membrane in capstan, disc, capacitor etc.As good lay-by material, biaxial stretch-formed up to 5X or 7X for these films, this will make its characteristic obvious especially.

When stretching a volume film with stenter of the present invention, have been found that this have active and driven carriage, and these dollies can stay a distinctive catcher mark with draw ratio that surpasses about 3X and the stenter that is pushed into the port of export speed that surpasses 200 feet of about per minutes on improved film.When film left stenter, this catcher mark was significantly on the film crimping of thickening, and concerning this film product of only being produced for the first time by technology of the present invention, this catcher mark is unique.These initiatively are clipped in and leave stress trace line on the crimping, and this trace line from the centre of film to the edge towards film by the direction of longitudinal stretching at angle.Passive being clipped in left stress trace line on the crimping, this trace line film be stretched direction rightabout at angle.

Among Figure 15, represent by arrow 988, and with towards the film stretching direction at angle, this film stretching direction is by arrow 955 expressions by the general direction that initiatively presss from both sides the stress trace line catcher mark that stays.The general direction of the stress trace line catcher mark that is stayed by passive folder is by arrow 990 expressions, and with arrow 955 rightabouts at angle.

The stenter line loop

Figure 19 represents three projected relationship curves of little vehicle speed of clip and position, and these curves are used to simulate the simplification loop of stenter loop of the present invention.Be to simplify the analysis of system, the quantity of control area and length have reduced and have saved the control area and return gap between the side; The stable section of stenter has also saved.Article three, the purpose of curve is to illustrate three kinds of different film stretching line charts, how can by initiatively and the driven carriage propulsion system be regulated, and how particularly different line charts influences and returns side initiatively and driven carriage deceleration and dolly gathering.Dotted line is represented the velocity of electromagnetic wave for each curve of little vehicle speed among Figure 19.The velocity of electromagnetic wave that numeral 1,2 or 3 expressions and its curve interrelate, curve 260 is associated with numeral 3; Curve 262 is associated with numeral 2; Curve 264 is associated with numeral 1.Curve 260 expressions have the stenter processing longitudinal stretching ratio of (33.3 λ/per second)/(11.1 λ/per second) or 3.0X; The longitudinal stretching of curve 262 is than being 44.4/11.1 or 4.0X, and the longitudinal stretching of curve 264 is than being 88.8/22.2 or 4X.Figure 25 is a figure of simplifying a representational loop of stenter.The curve that it is illustrated in representative relation between the medium and small vehicle speed of stenter loop of simplification and the dolly position is a wedge shape.

The core of speed and position relation curve is owing to the desirable duty of oriented film is predetermined.For example the introducing speed of reference curve 260 from 266 to 268 clips is also promptly piled row speed and is determined by film speed; Yet the speed of acceleration, final draw ratio and from 268 to 270 clips also is the needs that depend on film stretching.These parts of curve can be got many values and be adopted various forms, determine and can't help the linear motor system, therefore will not discuss at this.With reference to Figure 25, loop left area position position " a " corresponding to Figure 19 in regional location on the horizontal axis of curve, be advance side from " a " to " b ", return side from " b "-" c "-" d "-" e "-" f "-" a "." a " and promotes initiatively dolly until " b " to first primary coil from the position.By engaging with active dolly adjacency or with film, make driven carriage be advanced to " b " from " a ", this is carried by the active dolly.Film is clamped at " a ", is loosened at " b ", and to " c ", friction pulley advances initiatively dolly and driven carriage from " b ".Second primary coil, and advances initiatively and driven carriage until " d " from " c ".From " d " to " e " both do not had first primary coil not have second primary coil yet; Initiatively and driven carriage be adjacency at this, and " d " promoted by second primary coil of front the preceding, from " e " to " f " is the part of first primary coil, propelling active dolly; Driven carriage is promoted by the active dolly.From " f " to " a " both do not had first primary coil not have second primary coil yet, and active and driven carriage are pushed through this part.

On curve 260, dolly enters stenter and becomes at 266 places in abutting connection with the heap row.Are heap row ports of export at 268 places, dolly begins to quicken and separate herein, reaches final speed (33.3 λ/sec), and separate in 270 punishment up to them.Be illustrated as the draw ratio of 3X, before entering the secondth primary coil, hysteresis area 271 places, the dolly at 270 places is pushed into constant speed by friction pulley.Under lower draw ratio 3X, a large amount of dollies is in advance side, and therefore, the speed of returning side must keep higher, so that make remaining dolly get back to heap row arrival end apace.Therefore, in control area 276, the speed that electromagnetic speed will reach with 33.3 λ/seconds makes dolly be able to continuous propelling.In control area 278, this electromagnetic speed remains unchanged.In control area 280,, dolly is reduced speed now by velocity of electromagnetic wave being reduced to about 26 λ/seconds.Before 280 ends of control area, the speed of idle pulley and motor-bug drops to about 24 λ/seconds, like this, no matter the minor variations of rate of deceleration, all dollies reached approximately identical speed before leaving control area 280, and these dollies enter next area operation with this predictable speed.Therefore, the various conditions that enter any magnetic hysteresis control area at these dollies are known constant, and regional to the next one from a control area, and the minor variations of speed is not superimposed.In control area 282, dolly slows down when entering the control area once more, and reaches a balancing speed, and before dolly reached heap row upstream end 288 places, control area 282 positive applied thrusts were to overcome the friction of dolly.Importantly, inlet heap row section always appears at dolly and leaves before second primary coil.Actual heap row arrival end can appear at two gap locations between the magnetic hysteresis control area, or within magnetic hysteresis control area.Last magnetic hysteresis control area preferably always is full of dolly so that produce enough heap row power, compressing the dolly damper, therefore at starting end 266 places of the first primary coil control area 261, make dolly on suitable spacing so that mate with electromagnetic wave.

In some cases, may wish 286 places in Figure 19 and Figure 10, the Synchronization Control zone of a weak point is set, this is equivalent to first primary coil 975 among Figure 10, this 261 provides a power that helps the first few dolly in the control area, and these several dollies apply first tension force to the film of stenter arrival end.Control area 261 corresponding to the control area A(coil 930/930 among Figure 10 ').Two synchronous secondary coils on each the active dolly that in control area 286, engages, the power that in the space of compactness, produces, more much bigger than the power that the single magnetic hysteresis secondary coil on active in control area 282 and the driven carriage produces.Preferably force servicing unit with this because in order to keep the tension force of introducing in the film, in transportation section 918 (Figure 10), to first initiatively dolly carry out any pressure and move all and may cause slight stretching, be undesirable at this.

Curve 262 is illustrated in and returns side, and higher draw ratio 4X is to the result of 3X.In this case, more active and driven carriage move to returns side, and like this, their energy is removed through short distance, so that adapt to long heap row length.Control area 280 is used for lower velocities of electromagnetic wave (promptly from the lower frequency of its driver) work of curve 260 with a ratio, and therefore, decelerations of all pre-heap row occur in this control area, control area 280 with 282 with identical velocity of electromagnetic wave work.Owing to have more secondary coil to be in this higher draw ratio returning side, thus heap row length increase a little, as along loop from curve on 260 288 to the curve 262 the 284 heap row arrival ends that back move certified.

The scale up result of linear velocity of curve 264 expression, at this moment keep the extensibility identical with curve 262, because dolly enters and returns the result that side speed is higher so energy is higher, decelerative force must be applied on active and the driven carriage, so that early reached a low impact velocity before their arrive the arrival end of piling row.Notice that the energy percentage that consumes increases, so that reach low speed collision speed in each control area.This energy percentage be decelerative force F(it be the power of the calculating of deriving according to the magnetic hysteresis secondary coil) take advantage of length δ L(on this length, to slow down) (Fx δ L); The power F identical with the total length that is equivalent to each control area (FXL) is similar.If the control area is unequal length, but work under the same electrical flow valuve, in than the LCR territory, the gross energy of possible loss will be bigger.Reference curve 264 because dolly slows down on long length δ L, is increased at the energy percentage of each control area internal loss.Because the result of this different deceleration line charts holds 284 places relatively with the heap row of curve 262, the heap of curve 264 row end 290 places are shorter, although these two curves are the dollies that are used to return equal number on the side.Two extreme, heap row arrival end necessarily always appears at before the end that arrives last magnetic hysteresis control area and enters before any Synchronization Control zone; And after dolly reached final balancing speed, certain distance necessarily appearred in the heap row.This final balancing speed is considered to heap row hypervelocity.Dolly is caught up with the speed of heap row should be always sufficiently high, but when the speed of colliding the heap row when the numerical value that causes initiatively and driven carriage is damaged is following, the speed that maintenance is collided should be always enough low.

Claims (19)

1, a kind of method of using the linear motor drawing plastic film in stenter comprises the following steps:

In paired symmetrical opposed loop,, advance the active dolly with this film that stretches with the stenter folder that is connected on the dolly at a predetermined velocity in the processing film section of stenter;

Form the heap row of dolly; And

Enter at dolly before the processing film section of stenter, advance the heap row of dolly in the dolly collection sections.

2,, use syncmotor this film that stretches according to the process of claim 1 wherein.

3,, use hysteresis motor dolly to be pushed the heap row of dolly according to the process of claim 1 wherein.

4, according to the process of claim 1 wherein that syncmotor was used for before dolly enters the processing film section of stenter, in the dolly collection sections, with first controlled velocity propulsive units dolly heap row.

5, according to the process of claim 1 wherein, also comprise the following steps:

Advance opposed dolly in dolly collection sections and processing film section in pairs, and use syncmotor to make dolly advance paired dolly by the processing film section from one first speed to the second speed greater than first speed, these paired dollies are spaced apart thus;

Form section propelling dolly spaced apart and be listed as the formation section at the heap row, wherein before these dollies arrive the dolly collection sections, use hysteresis motor dolly to be pushed the dolly that is just moving with first speed and pile the row from second speed by heap.

6, according to the process of claim 1 wherein, between the active dolly in each loop, at least one driven carriage is set, and these driven carriage do not add power during the film stretching step.

7, according to the method for claim 6, wherein, the employing hysteresis motor is being piled the propelling of row formation section these active and driven carriage, and a heap that enters dolly by this heap row formation section is listed as.

8, a kind of linear motor that uses comprises the following steps: by the method that is connected to initiatively and the stenter on the driven carriage presss from both sides drawing plastic film

One is connected on each active dolly with a magnetic hysteresis secondary coil synchronously;

A driven carriage is arranged on each initiatively between the dolly;

A magnetic hysteresis secondary coil is connected on each driven carriage;

Along the advance side of a pair of opposed closed circuit, the first linear motor primary coil is provided, adjacent this first primary coil that is provided with synchronous secondary coil, and it is connected with oriented film with synchronous secondary coil on the dolly initiatively;

The side of returning along each loop provides second primary coil, and initiatively and adjacent this second primary coil that is provided with of magnetic hysteresis secondary coil on the driven carriage, and is connected with magnetic hysteresis secondary coil on the driven carriage with active, so that dolly is turned back to the advance side of loop.

9, in stenter, the control method in a kind of dolly heap row that many isolated actives and driven carriage pushed mobile adjacency comprises the following steps:

Advance the dolly heap row of adjacency with first speed;

Before dolly arrives the heap row, by using the magnetic hysteresis linear motor, advance isolated dolly with second speed greater than first speed, enter and the controlled collision adjacency state of dolly heap row of adjacency.

10, linear motor of a kind of use makes with constant rate of speed and has the method that many dollies two kinds of different qualities, that move along an elongated passageway quicken, and comprises the following steps:

One first magnetic hysteresis secondary coil is connected on one first dolly, and this secondary coil has the size that is directly proportional with the quality of first dolly;

Along this passage a linear motor primary coil is set, and with the adjacent setting of the first and second magnetic hysteresis secondary coils;

The first and second magnetic hysteresis secondary coils are engaged with an electromagnetic wave that is produced by primary coil, and this electromagnetic wave is propagated with the speed that is different from many little vehicle speeds, thus all dollies is quickened with substantially the same not variable Rate.

11, by using linear motor in the opposed loop that limits by a pair of vehicle guide opposite each other, advance a kind of device of rolling up plastic sheeting that stretches of each dolly with the stenter folder that connects on it at a predetermined velocity, it comprises:

The first elongated primary coil is placed on the advance side of loop opposite each otherly.

The second elongated primary coil is placed on the side of returning of loop opposite each otherly.

Many active dolly surround orbits are directed, has the adjacent setting of each dolly that connects a synchronous secondary coil on it with first primary coil, be used in a processing film section of stenter, synchronously advance these active dollies at a predetermined velocity in couples so that the film that stretches and clamp by stenter;

Each initiatively adjacent setting with second primary coil of dolly with magnetic hysteresis secondary coil that connects on it is used for forming section at the heap row and advances an initiatively dolly, and forms section by these heap row and enter and return dolly on the side at loop and pile and be listed as.

12, according to the device of claim 11, wherein, in each loop each initiatively is provided with at least one driven carriage between the dolly, has the adjacent setting of each such driven carriage that connects a magnetic hysteresis secondary coil on it with second primary coil, be used for forming in the section and advance driven carriage, and form section by these heap row and enter loop and return during dolly heap on the side is listed as at heap row.

13, a kind of in the opposed closed circuit of a stenter, use a linear motor to advance the control method of many dollies with oriented film, wherein this loop has advance side opposite each other and return side, and dolly has the film folder that connects on it, and this method comprises the following steps:

With a linear motor synchronously and the magnetic hysteresis secondary coil be connected on each dolly of oriented film on one's own initiative;

A linear motor magnetic hysteresis secondary coil is connected on each dolly of handle thin films passively, these driven carriage are arranged between the adjacent active dolly;

Along the advance side of each loop and the adjacent first linear motor primary coil that is provided with of synchronous secondary coil of dolly initiatively, and along each loop return side with initiatively and the adjacent second linear motor primary coil that is provided with of magnetic hysteresis secondary coil of driven carriage;

First primary coil is arranged in each loop, so that comprise many coil groups, make that opposed coil groups is complementary in the primary coil of its coil groups in the primary coil of a loop of sizing and another loop, and its each opposed coil groups is electrically connected and has determined a single control area;

Second primary coil is arranged in each loop, so that comprise many coil groups, make that opposed coil groups is complementary in the primary coil of its coil groups in the primary coil of a loop of sizing and another loop, and its each opposed coil groups is electrically connected and has determined a single control area;

Encourage the control area in a predefined manner, dolly is engaged, and advance initiatively dolly, and advance initiatively and driven carriage along the thruster of returning of the loop of substantial symmetry along the advance side of the loop of symmetry in pairs.

14, a kind of have advance side and returning the method for initial many dollies in the closed circuit of side, and wherein these dollies are advanced by a linear motor, and this method comprises the following steps:

With one synchronously and magnetic hysteresis linear motor secondary coil be connected on these dollies;

Along the advance side of loop and secondary coil synchronously are adjacent one first linear motor primary coil is set, and returns along loop that side is adjacent with the magnetic hysteresis secondary coil to be provided with second primary coil;

Make the beginning part de-energisation of advance side first primary coil;

A low DC current is applied to the second portion of advance side first primary coil, to engage dolly there regularly;

Encourage the remainder of advance side first primary coil and return side second primary coil, to advance remaining dolly and to make dolly become adjacency, this being activated at provides a power on the remaining dolly, this power is less than that power of the dolly of adjacency in the beginning part that is bonded on advance side regularly;

A DC current is applied to the beginning part of first primary coil;

Encourage second and remainder and second primary coil of first primary coil, in order to these dollies are released this second and remainder, and make these dollies become adjacency;

Encourage first and second primary coils, to advance these dollies continuously along closed circuit.

15, a kind of have advance side opposite each other and returning in a pair of opposed closed circuit of side, and the method for initial many dollies wherein advances these dollies by a linear motor, and this method comprises the following steps:

With one synchronously and magnetic hysteresis linear motor secondary coil be connected on these dollies, these dollies that replace have the synchronous secondary coil of opposite polarity;

Along opposed advance side of loop and the synchronous adjacent first linear motor primary coil that is provided with of secondary coil, and return adjacent second primary coil that is provided with of side with the magnetic hysteresis secondary coil along the loop;

Make the beginning part de-energisation of each first primary coil;

A low DC current is applied on the second portion of each first primary coil, to engage dolly there regularly;

Encourage the remainder and second primary coil of first primary coil, to advance remaining dolly, and make these dollies become adjacency, and this being activated at provide a power on the remaining dolly, and this power is less than that power of the dolly of adjacency in the beginning part that is bonded on first primary coil regularly;

One high DC current is added on the second portion of first primary coil;

One direct current electric current is applied on the beginning part of first primary coil;

Make the second portion de-energisation of first primary coil;

The polarity of detection secondary coil of leading dolly in the beginning part of one of loop;

Advance dolly in the beginning of loop part step by step till detecting required polarity secondary coil;

The polarity of detection secondary coil of leading dolly in the beginning part of another loop;

Advance dolly in the beginning of another loop part up to leading dolly secondary coil polarity and being complementary in that loop step by step;

Encourage second and remainder and second primary coil of first primary coil, so that dolly is released second and remainder, and make dolly become adjacency;

Encourage first and second primary coils of two loops simultaneously, so that advance these dollies continuously along symmetrical in pairs closed circuit;

16, a kind of film folder of making breaks away from, and dolly is entered the method for returning side of a closed circuit of a stenter from the film stretching thruster, comprises the following steps:

Provide a wheel across at the terminal of film stretching side with return the beginning between the place of side, this wheel is used for the bonding film folder, with first diameter that opens it be used for engaging dolly with second diameter with its propelling;

At arc place with a center, dolly is directed to from the end of film stretching side returns beginning of side, the center of this center and first and second diameters and is used for making the dolly location that engages second diameter in line;

Rotate this with a speed and take turns, so that the second diameter circle circular velocity is approximately with identical at the little vehicle speed of film stretching side end.

17, a kind of in closed circuit, use to have a linear motor that is connected to the synchronous and magnetic hysteresis secondary coil on the dolly, control the operation that moves of many dollies.

18, a kind of in having a stenter of a linear motor, use to have the operation that stenter synchronous and that the magnetic hysteresis secondary coil is connected thereto presss from both sides the volume film that stretches.Wherein, when stenter folder oriented film, by synchronous secondary coil these clips are advanced in the loop of paired symmetric position, and when the stenter folder breaks away from film, these clips are advanced in this loop by the magnetic hysteresis secondary coil.

19, twin shaft ground oriented film comprises simultaneously:

Have one of thicker crimping along two longitudinal edges and approach bar, the crimping with catcher mark, during stretching, film is clamped in this catcher mark place, and wherein catcher mark comprises:

Many first catcher marks, each catcher mark have film by the direction of longitudinal stretching on angled stress trace line;

Second catcher mark that occurs between first catcher mark, each second catcher mark have in contrast to film by angled stress trace line on the direction of longitudinal stretching.

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